Princes Channel Wreck - Phase iii

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Wessex Archaeology

Princes Channel Wreck,

Thames EstuaryPhase III Summary Report

January 2005

Ref: 57330.01


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PRINCES CHANNEL WRECK, THAMES ESTUARY

MITIGATION STRATEGY:

PHASE III RECORDING AND RECOVERY

SUMMARY REPORT

Prepared by:

Wessex ArchaeologyPortway House

Old Sarum ParkSalisbury

WILTSHIRESP4 6EB

Prepared for:

Port of London AuthorityBakers Hall

7 Harp LaneLondon

EC3R 6LB

December 2004

Ref: 57330.01

The Trust for Wessex Archaeology Limited 2004

The Trust for Wessex Archaeology Limited is a Registered Charity No.28778


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SUMMARY REPORT

Ref: 57330.01

Executive Summary

Wessex Archaeology (WA) has been commissioned by the Port of London Authority (PLA)

to mitigate the impacts of dredging operations on a late 16

th

century shipwreck located withinthe Princes Channel, Thames Estuary.

The mitigation of impacts for the Princes Channel Wreck site is being approached in a seriesof phases. Phase I relates to remedial recording of timbers, sections of recovered hull (pieces 1

and 2) structure and artefacts recovered in 2003. Phase II relates to a programme of scientificdating, geophysical survey and diving inspection undertaken in 2004.

Phase III began with the development of a Project Design which was submitted to the EnglishHeritage Maritime Team by the PLA in July 2004. EH approval for the Project Design was

received in early August 2004.

This document is a summary report of the fieldwork to excavate and recover the wreck in

August-October 2004 to fulfil Phase III of the overall mitigation strategy.

Over a period of 9 weeks, 27 dives were undertaken on the wreck site to locate timberstructure, excavate the overlying deposits and recover both artefacts and timber. 110 artefacts

were recovered ranging from cast iron cannons, lead and tin ingots to more personal itemssuch as a pewter candlestick, leather shoes and the sleeve of a jerkin.

One of the cannon has the makers mark of Sir Thomas Gresham and is believed to have beencast at the Mayfield furnace, East Sussex, between 1567 and 1582. Sir Thomas Gresham was

a prominent Tudor merchant and financial advisor to Henry VIII, Edward VI and Elizabeth I,and is famous for the founding of a money exchange (Royal Exchange) in London in 1565.

Three large sections of hull structure were recovered. Pieces 3a and 3b forming part of the

ships side, with Piece 4 being the ships bow section including articulated keel to stempost.

The nature of the recovered timber structures confirms the findings of WAs earlier reports.

The vessel had a keel length of 20m to 30m and a possible overall length of up to 35m. Anumber of English merchantmen, depicted in a manuscript, believed to have been authored by

the shipwright Matthew Baker in the 1570s (Baker, ca. 1570 1630), are the closestavailable representation of what the Princes Channel ship may have originally looked like.


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The vessel was probably three-masted, although no elements of rigging have been found. The

lowest deck in the ship, the orlop, served as a gundeck. Two gunports are visible in therecovered hull structure above the main wale. A total number of six to eight gunports per side

can be assumed.

Although still unidentified, it is thought that the ship was possibly outbound from London or

another harbour on the Thames or Medway with a cargo of iron bars, lead ingots and tiningots. The locations of the cannon on the seabed are suggestive of armament rather than

cargo, as they appear to correspond with the level of the gunports on the ships side.

The excavation of the Princes Channel wreck concentrated on the core of the wreck site andthe main aim was to lift the timber structures and artefacts in this area. Although circular

seabed searches were conducted to a distance of 30m around the wreck in situ, not all of this

area was airlifted and fully excavated. The wider surroundings of the wreck site (side scantargets were marked in a distance of up to 70m from the wreck) could not be examined in the

course of the Phase III project. The presence of further archaeological material within theseabed cannot be excluded.

The quality and quantity of timbers and artefacts recovered warrants post-excavation analysis

and publication, in accordance with the further phases set out in the Project Design:

Phase IV: Post Excavation Assessment

Phase V: Analysis

Phase VI: Treatment of timbers/ artefacts

Phase VII: Publication

The research framework outlined in the Mitigation Strategy Project Design should be revisitedand revised to establish parameters for further analysis of the timbers and all recovered

material.


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SUMMARY REPORT

Ref: 57330.01

Acknowledgements

This project was commissioned by the Port of London Authority. Wessex Archaeology would

like to thank the PLA Marine Services, especially Captain Peter Steen, Marine ServicesManager, Kevin Leadbetter, Marine Services Diving Supervisor and his dive team, Steven

Rushbrook, Marine Services Assistant and the crew of the PLA Salvage VesselHookness fortheir support throughout the project. Further thanks go Nicola Clay, Environmental Scientist;

Mike Costaras, River Engineer; and Captain John Pinder, the Port Hydrographer.

The diving fieldwork was carried out by Jens Auer, Rex Bangerter, Frank Mallon and Nigel

Nayling of Wessex Archaeology. Diving support and the dive vessel crew were provided bythe PLA Marine Services dive team. Kevin Leadbetter acted as Diving Supervisor. The land-

based recording of the lifted wreck parts was undertaken by Kitty Brandon, Bob Davis,Gareth Owen and Matt Rous.

This report was compiled by Jens Auer. The illustrations were produced by Kitty Brandon andGareth Owen. The project was managed for Wessex Archaeology by Deanna Groom and

Steve Webster. Quality assurance was provided by Dr. Antony Firth, Head of Coastal andMarine Projects.


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SUMMARY REPORT

Ref: 57330.01

Contents

1. INTRODUCTION............................................................................................... 1

1.1 Phase III ..................................................................................................... 11.2 Previous fieldwork..................................................................................... 1

2 AIM AND OBJECTIVES .................................................................................. 3

3 METHODOLOGY ............................................................................................. 4

3.1 Diving.......................................................................................................... 4Environment ................................................................................................ 4

Diving Vessels ............................................................................................. 4Mooring System ........................................................................................... 4

Diving Operations ....................................................................................... 5

3.2 Underwater recording............................................................................... 6

3.3 Underwater excavation ............................................................................. 7

3.4 Recovery of artefacts ................................................................................. 7

3.5 Recovery of timber structures.................................................................. 7

3.6 Shore-side recording of finds and dis-articulate timbers ...................... 9

3.7 Shore-side recording of timber structures .............................................. 9

3.8 Environmental samples........................................................................... 10

4 RESULTS .......................................................................................................... 11

4.1 Diving........................................................................................................ 11

4.2 Artefacts and dis-articulated timbers.................................................... 11

4.3 Timber Structures ................................................................................... 13

5 CONCLUSIONS ............................................................................................... 14

6 FURTHER WORK........................................................................................... 15

6.1 Site............................................................................................................. 15

6.2 Recovered Assemblage............................................................................ 15

REFERENCES ........................................................................................................... 16

APPENDIX I: MITIGATION STRATEGY PROJECT DESIGN........................ 19

APPENDIX II: DIVING UNDERTAKEN............................................................... 43

APPENDIX III: LIST OF GENERAL CONTEXTS.............................................. 48

APPENDIX IV: LIST OF FINDS............................................................................. 49

APPENDIX V: LIST OF ENVIRONMENTAL SAMPLES .................................. 53

APPENDIX VI: LIST OF TIMBERS BY STRUCTURE SUB DIVISION.......... 54


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Figures

Figure 1: Map of wreck position with integrated side scan data

Figure 2: Plate 1: Tug Impulse, used as diving platform

Plate 2: Diving equipment on Impulse

Figure 3: Site plan of wreck site, including underwater drawing of Piece 3 in situ, estimated position of pieces

1, 2 and 4 and all measured small finds

Figure 4: Plate 1: Lifting of iron bars

Plate 2: Lifting of piece 4 with the PLA salvage craft Hookness

Figure 5: CAD drawing of piece 4, internal and external

Figure 6: CAD drawing of Piece 3a, internal

Figure 7: CAD drawing of Piece 3a, external

Figure 8: CAD drawing of Piece 3b, internal

Figure 9: CAD drawing of Piece 3b, external

Figure 10: Reconstruction of ships side with pieces 1 4

Figure 11: Plate 1: Iron bars

Plate 2: Lead ingot

Plate 3:Tin ingot

Figure 12: Cast-iron cannon (28)

Figure 13: Plate 1: Leather shoe sole

Plate 2: Pewter Candlestick

Figure 14: Drawing of an English galleon ca. 1572-1600 by Matthew Baker, from Fragments of Ancient

English Shipwrightry, Pepys Library, Magdalene College, Cambridge. Inset: Reconstruction of ship's

side with pieces 1-4


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SUMMARY REPORT

Ref: 57330.01

1. INTRODUCTION

1.1 Phase III

1.1.1 Wessex Archaeology (WA) has been commissioned by the Port of London Authority

(PLA) to produce and implement a project design to fulfil the PLAs responsibility to

mitigate the impacts of dredging operations on an late 16th

century shipwreck locatedwithin the Princes Channel. The dredging operations will remove approximately 2m

of sediment in the Channel and from the nearby Shivering Sands to enable largeshipping traffic to utilise the Thames Estuarys southern approaches to the Port of

London.

1.1.2 The mitigation of impacts for the Princes Channel Wreck site is being approached ina series of phases. Phase I related to remedial recording of timbers, sections of

recovered hull structure and artefacts recovered in 2003 (Wessex Archaeology 2003and Wessex Archaeology 2004b). Phase II related to a programme of scientificdating, geophysical survey and diving inspection undertaken in 2004 (Wessex

Archaeology 2004a).

1.1.3 Phase III began with the development of a Project Design submitted to the EnglishHeritage Maritime Team by the PLA in July 2004 (Appendix I). EH approval was

received in early August 2004.

1.1.4 This document is the summary report of the excavation and recovery of the wreck inAugust-October 2004.

1.1.5 All recovered material was notified by the PLA to the Receiver of Wreck, inaccordance with section 236 of the Merchant Shipping Act 1995, on the basis ofinformation provided by WA. Recovered material is held by the PLA to the order of

the Receiver.

1.2 Previous fieldwork

1.2.1 The Princes Channel wreck was discovered during a pre-dredging magnetometersurvey in April 2003. An inspection carried out by the Port of London Authority

(PLA) Marine Services dive team on 28 May 2003 identified a wooden shipwreckand metal objects. On 18 June 2003 some iron bars were recovered and an attempt

was made to disperse the site, but this proved unsuccessful. Subsequently, the grab


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barge Cherry Sand carried out wreck removal operations on 12 July 2003. The

recovered material included a large amount of timbers, iron bars, an anchor and acannon. A diving inspection by the PLA at the end of removal operations suggested

that the seabed was clear of obstructions. Navigational dredging operations that were

underway in Princes Channel at the time had been excluded from the area of thewreck to avoid damage to dredging equipment. As the seabed appeared to be clear,

the exclusion zone was removed and trailer suction dredging occurred in the vicinity.

1.2.2 Wessex Archaeology was contacted by PLA on 14 July 2003. A brief inspection wascarried out of the recovered material, which noted a possible second cannon among

the iron debris. As a result, WA was commissioned to carry out remedial recordingof the timbers and iron artefacts, which took place on 14-15 August 2003 (Wessex

Archaeology 2003). The timbers were interpreted as being from a vessel of up to200t burden, with a construction date between 1600 and 1850. The two cannons were

dated to the early 16th

century and to the 18th

century.

1.2.3 At this point the PLA believed that the wreck had been completely recovered ordispersed. However, when the PLA survey vessel Verifiercarried out a monitoring

survey of the dredged channel on 28 October 2003, topographic high spots were

noted about 30m from the original obstruction. A diver inspection confirmed theexistence of another piece of wooden wreckage. As a result of this discovery, Wessex

Archaeology was commissioned to carry out a diver inspection of the wreckage on 6November 2003. The WA divers observed a piece of hull structure, measuring

approximately 6.5m by 3m.

1.2.4 A side scan sonar survey undertaken on the same day showed the piece of hullstructure, but also further wreckage to the west that probably represented the original

site.

1.2.5 As the newly discovered section of hull structure was believed to be a hazard to

navigation, the decision was made to recover it. The lifting operation was carried outon 20 November 2003 by PLA staff with Wessex Archaeology in attendance. The

hull structure, which came apart in the course of the lifting operation (Piece 1 and

Piece 2), was stored at Denton Wharf, Gravesend.

1.2.6 On 3 December 2003 a Wessex Archaeology dive team conducted a diving

inspection of the original wreck site. Two separate sections of ship structure wereobserved on the seabed. One of the sections was covered in iron artefacts (bars). A

fragment of a Spanish olive jar was recovered during the dives.

1.2.7 The two recovered pieces of hull structure, Piece 1 and Piece 2, were recorded byWessex Archaeology between 19 and 23 January 2004. Elements of the construction

observed during the recording process suggested a date of building in the 16th

centuryand a possible Iberian influence upon the construction (Wessex Archaeology 2004b).

1.2.8 At this point the recovered assemblage consisted of 136 timbers, irons bars, an

anchor with wooden stock, a fragment of Spanish Olive jar, a 16th

century wrought-iron cannon and what was believed to be an 18

thcentury cast-iron cannon (pers. com.

Royal Armouries).


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1.2.9 To provide a firm basis for the development of the mitigation strategy, the scientific

or absolute dating of the timbers and the further characterisation of the materialremaining on the seabed were necessary to complete the evaluation phase.

1.2.10 Dendrochronological dating of 12 samples taken from frame components on the

previously lifted Pieces One and Two took place on 6 May 2004.

1.2.11 The results indicate a date of building for the ship in or shortly after AD 1574. Themost likely origin of the oak timbers is eastern England, particularly East Anglia and

Essex (Nayling, 2004).

1.2.12 A high-resolution side scan survey of the site was undertaken on the 25 May 2004.The survey resulted in a georeferenced mosaic of the site, which was used to identify

targets around the main wreck site and to plan phase III of the mitigation process

(Figure 1).

1.2.13 A further diving inspection of the site, undertaken on the 14 16 June 2004 served toassess the overall disposition of major structural elements and their depth of burial

and to assess the presence and distribution of artefacts on the site.

1.2.14 The results of the previously mentioned phase II surveys were presented in an

Evaluation report (Wessex Archaeology, 2004a)

2 AIM AND OBJECTIVES

2.1.1 The aim of the project was to mitigate the impacts of the Princes Channel dredging

activity on the wreck site.

2.1.2 The project objectives for the fieldwork in phase III were:

to complete a baseline survey of the archaeological material remainingon the seabed;

to excavate and recover disarticulated / dispersed timbers andartefacts;

to excavate and recover wreck deposits, environmental samples and

large structural fragments (Piece 3 and 4)

to record individual timbers and timber structures at a shoresidefacility, using conventional methods and 3D digital survey methods

to collate, check and cross-reference the digital and hard copy archive.


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3 METHODOLOGY

3.1 Diving

Environment3.1.1 The site is located in Princes Channel c. 17km from Whitstable. The site is exposed

and subject to tidal currents of up to 3 knots.

3.1.2 Phase III operations commenced on 16 August 2004 and were originally planned to

take 20 days in two blocks of 10 days with an intervening break coinciding with the

August bank holiday.

3.1.3 Adverse weather severely disrupted this programme with the result that operations

took place intermittently over a nine week period with the final diving taking place

on 16 October 2004. Shore-side recording, originally planned to take place once

diving was completed, actually took place from 14 September to 22 October 2004, inorder to make use of diving downtime.

Diving Vessels

3.1.4 In the course of the project, two different diving support vessels were employed.Impulse, a river tug, was used from the start of the project until 11 October 2004. Thetug was equipped with a 1 ton crane and provided enough deck space to run a

compressor for the airlift work and an LP compressor for the diving air supply

(Figure 2, Plate 1).

3.1.5 The diving control panels, the underwater video panel and the diver communication

units, as well as the navigation laptop were set up in the wheelhouse. All equipment

was stored either on deck, in the engine room or in the aft stores.

3.1.6 At the start of the project, Impulse was equipped with a DGPS for navigation and an

echosounder.

3.1.7 To minimise the travelling time to site, Whitstable harbour was chosen as a base for

the diving operations.

3.1.8 Impulse was transferred back to Gravesend on the 11th

October after a prolonged

period of bad weather. All further diving operations were carried out from

Gravesend, using the PLA Marine Services dive boat PLA Diver. This vessel was not

equipped with a crane and did not have the capacity to carry an airlift compressor, sothat the diving work was limited to seabed surface searches. Diving operations couldhowever be run from the wheelhouse with a similar set-up to that onImpulse.

Mooring System

3.1.9 In order to maintain the position of the diving vessel over the site in the course of thediving operations, a mooring system was required. As any obstruction left on the

seabed or on the surface in the Princes Channel was seen as a hazard to navigation, amooring system that avoided surface markers had to be devised.

3.1.10 The mooring solution consisted of two sinkers of two and three tons respectively,

positioned upstream and downstream of the wreck. Both sinkers were positioned


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close to the wreck (6m to 10m) to allow the tug to stay directly above the site when

moored.

3.1.11 The sinkers were not marked on the surface. Instead, the steel cables connected to thesinkers lead to a guide cable, long enough to reach the edge of the Princes Channel.

This cable had to be dragged out of the navigational channel at the end of each divingday, where it was deposited with a 56pd weight next to a yellow marker buoy.

3.1.12 At the beginning of each diving day, the end of the steel cable was picked up, the

guide cable hauled inboards and the two mooring wires split and made fast at bowand stern respectively.

3.1.13 To allow accurate positioning of the tug over the site, the boat position was displayed

over a high-resolution side scan image of the wreck in the navigation package ESRI

Arcpad. This software allowed distance and bearing to the site to be measured. Thuscorrections to the boat position during the mooring could be made, and shots could

be dropped directly on the wreck site.

3.1.14 During the first two weeks of the project, when diving operations were conducted inwind conditions up to force 4, a number of problems were encountered with the

mooring arrangement. The mooring wires tended to get entangled around the wreckon the seabed, damaging parts of the timber structure. In addition the mooring wires

broke in heavy swells.

3.1.15 These problems were solved by a change in diving policy. Dives were onlyconducted in winds up to force 3. The original mooring cables were substituted by

heavier grade wires. At the beginning of each dive day, the two mooring wires were

picked up, but left slack. A diver then went down along the wires to check whetherthey were clear. The diver stayed in the water and ensured that the wires stayed clear

of the timber structures while the tug moored.

3.1.16 Nevertheless, the mooring and guide wires caused damage to the wreck site on twooccasions, when passing ships picked up the mooring arrangement and pulled the

cables through the wreck site. On one of these occasions, Piece 3 was broken intotwo pieces. The second time, Piece 3b, which remained in situ on the seabed, was

pulled from its original location and flipped upside down.

Diving Operations

3.1.17 All diving operations were conducted using surface supplied equipment. An LP

compressor provided the air supply with a number of HP cylinders as backup.Umbilicals were stored on the working deck.

3.1.18 The dive team consisted of seven members as follows: one skipper and diving

supervisor, one archaeological supervisor, one standby diver, two tenders and two

divers. Under normal conditions the two divers were in the water at the same time,with one standby diver and two tenders on deck.

3.1.19 One of the divers used a KMB 27B diving helmet with surface controlled light and

head-mounted digital video camera (Figure 2). The second diver was equipped witha KMB 18 bandmask with a battery-powered light attached. The divers descended to

site on a temporary shot or along the mooring cables. A diving ladder provided a safe


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entry- and exit point on the tug. The divers carried compasses for underwater

orientation.

3.1.20 The PLA diving supervisor was in charge of pre-dive checks, descent and ascent.During the dive the archaeological diving supervisor controlled the two diver

communication units and the DV camera.

3.1.21 Dives could only be conducted during High Water and Low Water slacks. The waterdepth on site varied between 7m and 10m, depending on the tide. Maximum bottom

times during High Water spring tides could be as little as 30min to 45min, but inLow Water slacks during neap tides, dives of up to 200min length were possible.

Details of diving operations undertaken are set out in Appendix II.

3.1.22 All diving was conducted according to the PLA code of practice for diving

operations, which accords with the Diving at Work Regulations 1997.

3.2 Underwater recording

3.2.1 The visibility on site varied between absolute zero and 20 to 30cm. This made

underwater photography impossible and underwater drawing very difficult. Evenvideo mosaics, taken with the high-resolution digital video camera, proved an

insufficient means of visual recording.

3.2.2 In addition, any tape measures laid out as a part of grid systems on the timber

structures were swept away by the tide or ripped apart by the current between twoslack tides. Thus the decision was made to use the timber structure itself as a datum

system and establish only a few points on the seabed around the wreck to link dis-articulate artefacts to the timber structure once it was lifted.

3.2.3 All timber that could be seen or felt were tagged with unique numbers engraved on

yellow plastic survey discs. Subsequently measurements of sided frame dimensionswere taken along the eastern and western side of the Pieces 3 and 4. Finally,

measurements across the wreck along each frame linked both sides and allowed acomplete wreck plan to be plotted (Figure 3).

3.2.4 All measurements were relayed to the surface via the diver communication, noted,

and later plotted in 1:20. The resulting wreck plan allowed further contexts to bedefined for the mapping of small finds on the timber structure. Context numbers were

assigned to visible gaps between frames and to areas on the inside of the wreck. The

surroundings of the main wreck site were divided into a northern, an eastern, asouthern and a western context.

3.2.5 Positions of small finds on the timber structure were taken by context and timber

number: e.g. potsherd in context 125, on ceiling plank 1190 on top of frame 1163.The positions of small finds and dis-articulated timbers in the surroundings of the

wreck site were fixed with at least two measurements from the object to knowndatum points around the wreck, or frame heads on the timber structure. If this was

not possible distance and bearing measurements were used (Figure 3).

3.2.6 Originally it was intended to use an acoustic USBL diver tracking system in

conjunction with a recording database for the positioning of objects in thesurroundings of the wreck site. This system was set up in the first week of the


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project, but could not be used due to software and hardware failures that were not

resolved by the manufacturer. Due to the time constraints of the underwater work, itwas decided to demobilise the USBL system and to use the traditional recording

methods described above.

3.2.7 A full listing of contexts is presented in Appendix III.

3.3 Underwater excavation

3.3.1 The whole inside of the wreck in situ was systematically excavated by context beforelifting. Two airlifts were used to remove sediment. On some days the visibility did

not allow to the diver to see the muzzle of the airlift. To prevent loosing small finds,mesh bags were fastened to the end of each airlift, and exchanged when a new

context was excavated. The collected material was sieved on the surface.

3.3.2 For the removal of material around the timber structures airlifts without mesh bags

were used.

3.3.3 On the eastern side of the wreck, iron bars were concreted to the ceiling planks. To

be able to lift the bars without causing damage to the ceiling planks, a pneumaticchisel had to be used to loosen the concretion. Whenever larger parts of concretion

could be separated from the main body, they were lifted individually using the ships

crane.

3.4 Recovery of artefacts

3.4.1 All artefacts and loose timbers on the inside ofPiece 3 on the seabed were recovered

before the piece was lifted. Disarticulated material from the surroundings of the

wreck was also lifted.

3.4.2 On the tug Impulse, the 1 ton crane could be used to lift heavier finds, such as iron

bars or cannons. To enhance the workflow underwater, a cage was used for the

recovery of small finds (Figure 4, Plate 1). At the beginning of each dive the cagewas lowered to a position close to the divers on the seabed. All tools could then be

kept in the cage and finds could be lifted in the cage at the end of the dive. The cranewire also acted as a messenger line to site.

3.4.3 Delicate items, such as the leather shoe and part of a leather jerkin, were recovered

within a sample of their surrounding contexts and placed in sealed containers/plastic

bags underwater before being transferred to the cage for their final lifting to thesurface.

3.4.4 A full listing of recovered artefacts can be found in Appendix IV. This listingincludes artefacts recovered from the site during earlier phases of work.

3.5 Recovery of timber structures

3.5.1 Originally it was planned to lift each of the individual wreck pieces separately after a

measured in situ survey and the removal of all overlying sediment. However, onstarting Phase III operations, Piece 4 was found to have moved from its original

location and could not be located during the first two dives on site. Extensive circular


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HW slack. It was then transported to Gravesend, where it was unloaded into a barge

filled with water to prevent it from drying out, until it could be lifted onto the quayfor recording.

3.5.10 A full listing of recovered timbers can be found in Appendix VI. This listing

includes timbers recovered during earlier phases of work.

3.6 Shore-side recording of finds and dis-articulate timbers

3.6.1 After recovery, all finds and loose timbers were labelled, photographed anddescribed, either on board the tug or in the shore-side facility in Whitstable. Each

artefact and timber was assigned a unique number and was labelled with a yellowmarker disc. Then a number of digital photographs were taken. Descriptions were

entered in timber- and artefact recording sheets, as well as into an MS Access based

timber and finds database.

3.6.2 Very well preserved loose timbers or examples of functionally important timberswere also drawn in 1:10 on permatrace.

3.6.3 After recording, finds and timbers were stored in freshwater basins in a storagefacility in Whitstable harbour. The freshwater was regularly exchanged to prevent

growth of microorganisms, such as algae and fungi, and to help desalination.

3.6.4 Due to the amount of iron bars recovered, only the best-preserved examples were

kept wet. The majority was stored on palettes and left to dry out.

3.6.5 On the 14 October 2004, the majority of finds were transferred to another storage

facility at Wessex Archaeologys main offices in Salisbury. The palettes with iron

bars and the loose timbers remain in a freshwater basin and a barge at Denton Wharfin Gravesend.

3.6.6 Of the two cast-iron cannons, that were lifted in the course of Phase III, one was

carefully freed of concretion on the advice of the Royal Armouries before it wasrecorded. The removed concretion was retained. The other cannon was left

concreted. Both cannons were later transported to the Royal Armouries at FortNelson, Portsmouth for conservation.

3.7 Shore-side recording of timber structures

3.7.1 After initial storage in water filled barges, the three coherent pieces of wreck werelifted onto the quayside at Denton Wharf, where they were covered by plasticsheeting and kept wet with a leaky hose system. The plastic cover was only removed

for recording.

3.7.2 Before the start of the digital recording, each piece was carefully cleaned withfreshwater and soft brushes to reveal detail on the wood. Then each individual timber

was assigned a unique number and tagged with a yellow survey marker. In thisprocess, only full thickness repairs, such as graving pieces were considered as

individual timbers. Knot patches were noted, but not numbered.

3.7.3 Following this, all visible trenails, iron nails and notable features such as carpentrymarks, tool marks, etc. were marked with drawing pins. Pin colours were assigned


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according to the functional difference of the trenails (e.g. red: trenails fastening outer

planks to frames, green: trenails fastening frame components to each other, etc.).This system helped interpretation and served as a basis for the layering system in the

CAD software later on.

3.7.4 Recording was carried out manually, by completing timber record sheets for eachtimber and taking digital photographs, and digitally using a total station.

3.7.5 The timber record sheets contain information on timber type, basic dimensions, and

features, such as repairs, marks and toolmarks. Sketches could be made on the backof the sheets. All the information contained in the paper records was later entered

into an MS Access database.

3.7.6 A full photographic survey of the wreck was carried out, using a digital camera.

Altogether more than 500 pictures of the wreck pieces were taken. These give anoverview of the timber structure in general, and show details, which could be

rectified and displayed over the 3D model of the wreck in AutoCad.

3.7.7 A Leica TCRA 1105 reflectorless total station was used for the digital 3D survey ofthe timber structures. It could be used reflectorless with a red laser, or with a mini

prism for surveying detail in gaps between timbers.

3.7.8 The survey data was fed directly into a laptop running AutoCad with the TheoLtextension. This allowed the data to be drawn and visualised in real time. Any survey

errors could be detected on the screen and instantly corrected. As the surveys of theinsides and outsides of the timber structures had to be conducted separately,

reference points were put in to allow both sides to be joined at a later stage (Figures

5 - 9).

3.7.9 In Auto Cad, each individual timber was assigned a separate layer to avoid confusion

and allow integration with the timber database at a later stage. Iron fastenings were

also recorded on separate layers, as were treenails, according to their function.

3.7.10 In addition to the manual 3D survey, a new recording method, based on

photogrammetry was tested on the bow section (Piece 4). The results of this survey

are still pending.

3.8 Environmental samples

3.8.1 Altogether 20 environmental samples were taken from the wreck site. Samplesinclude sediment from the wreck site, caulking material, textile material and

brushwood. A surface covering found on the outside and inside of planks was alsosampled.

3.8.2 The sampling concentrated on aspects related to the construction of the vessel, such

as waterproofing materials and surface covering. However, sediment samples werealso acquired from undisturbed contexts underneath the cargo in the hull and between

frames underneath ceiling planks for possible pollen analysis.

3.8.3 All environmental samples are currently stored at the Wessex Archaeologys main

offices in Salisbury.


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3.8.4 A full listing of Environmental Samples is presented in Appendix V.

4 RESULTS

4.1 Diving

4.1.1 In the period from 16 August 2004 to 20 October 2004, 27 dives were conducted on

the site over 18 days of diving operations. Depending on the tidal situation, each divewas from 40 minutes to 180 minutes long (Appendix II).

4.2 Artefacts and dis-articulated timbers

4.2.1 Of the 110 artefacts recovered from the wreck during Phases I, II and III, 101 were

lifted in the course of the Phase III excavation. The majority of these finds arecurrently stored in freshwater tanks awaiting further processing.

4.2.2 The ships cargo most probably consisted of iron bars, lead ingots and tin ingots.

There could have been other cargo, but no archaeological evidence of this has beenfound as yet.

4.2.3 Two types of iron bars were found on the wreck site. The first type are narrow bars

with a square section measuring 30mm x 30mm are folded four times to an overalllength of 1.9m to 2m. The second type are wide bars have a rectangular section of

30mm x 80mm, and are only folded once to the same length as the narrow bars,

giving an unfolded length of ca. 4m. A few, well preserved bars still show clearhammering marks (Figure 11, plate 1).

4.2.4 The lead ingots are boat shaped and measure 60cm x 22cm x 12cm. They have anaverage weight of 100kg. Stamps are visible on the upper surface of each ingot(Figure 11, plate 2). The marks appear to have been hammered into the surface of

the ingot whilst it was cooling, hence they are likely to be the smelters mark ratherthan a merchants mark. Merchants marks are more likely to have been chiselled into

the ingot after trading.

4.2.5 The origin of the stamps has yet to be identified, but many overseas lead resourceswere owned by the church and tend to have marks which signify ecclesiastical

origins. A hypothesis might be developed that these are more likely to be from

mercantile sources, and perhaps English in origin. The supply of lead in this period

was surfeit in England, and much was exported to France and Spain. Lead was usedextensively in the recovery of silver in the new world by the Spaniards (Dr LynWillies, Peak District Mines Historical Society, pers com.).

4.2.6 The lead ingot shown in Figure 11, plate 2 appears to have a cut or arrow mark in

one end which would have facilitate a rope cradle to be fastened around the ingot forease of transport. The cradle would have enabled the ingot to be carried in a vertical

axis for ease of dropping down cargo hatches on board ship (Dr Lyn Willies, PeakDistrict Mines Historical Society, pers com.).

4.2.7 The tin ingots are fairly small and were probably originally stored in barrels. They

measure 520mm x 18/16mm in average and have a trapezoidal cross section (Figure11, plate 3).


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4.2.8 Apart from an anchor (212), which was recovered by a grab in 2003, very little of the

ships fittings or equipment survives. A number of rope fragments in concretions arepossibly part of the rigging. If contemporary with the wreck, a lead pipe (89) could

have been part of the vessel drainage system. A number of brick fragments ( 13, 87)

were recovered from the wreck surroundings. These are probably fragments of thegalley construction.

4.2.9 The locations of the two Phase III cannon on the seabed are more suggestive of

armament rather than cargo, as they appear to correspond with the level of thegunports on the ships side. To date, the ships armament is represented by three cast

iron cannons (28, 201, 219), one wrought iron cannon (220), part of an elm guncarriage (98) and the find of a pike shaft fragment with concreted iron pike head

(204).

4.2.10 On one of the cannons, the concretion was carefully removed to allow detailedrecording. The cannon measures 2200mm (1980mm + 220mm) and has a bore of

76mm. The initials T G, the numbers 8-0-0 and a moulded grasshopper arevisible on the first reinforce (Figure 12).

4.2.11 The grasshopper motif and the initial have enabled the identification of the

gunfounder, Sir Thomas Gresham, whose coat of arms contained a golden

grasshopper. Gresham owned a foundry in the Weald at Mayfield, Sussex from 1567to his death in 1579. He was involved in arms export and is known to have founded

guns for among others the King of Denmark (Teesdale, 1991, p.128ff.). After SirThomas death, the foundry was taken over by his wife, who continued to produce

guns until 1582.

4.2.12 The number 8-0-0 on the reinforce specifies the weight of the cannon as 8cwt(406.418kg). The bore of 76mm to 80mm would be typical for a minion (Roth,

1995).

4.2.13 Life on board is exemplified by artefacts such as leather shoes (35, 55, 88, 205, 206),a fragment of a leather jerkin (80), a pewter candlestick (14) and part of a bronze

vessel (208) (Figure 13, plates 1 and 2). In addition, a fragment of a Spanish olive

jar was found in phase II (215).

4.2.14 Concretions form the second largest group of artefacts recovered during the

fieldwork of Phase III. The concretion is made up of sand, shell particles and sea

plants. This material begins to build up on objects in saltwater environments as partof the corrosion process. With time, concretion covers the object, preserving it in a

hard protective shell. In many of the 22 concretions recovered during Phase III,objects like pewter spoons and pewter tableware are visible.

4.2.15 Due to the potentially delicate nature of the artefacts contained within them, the

recovered concretions were left unopened awaiting x-ray and the intervention of aprofessional conservator.

4.2.16 In the course of the excavation 12 loose timbers were recovered from the site (1205-1221). In most cases, the original location could be confirmed from the in situ wreckplan, and reconstruction would be possible.


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4.3 Timber Structures

4.3.1 Three coherent timber structures were recovered and recorded in the course of Phase

III.

4.3.2 Piece 4 is part of the bow construction of the vessel. It consists of a fragment of thekeel, which is joined to the stempost. On the inside, the stemson as well as the apron

are partly preserved. Two v-shaped frames are fastened to the apron on the inside. Inaddition one side timber survives on the portside. Broken trenails and trenail holes

indicate the positions of further frames/ breasthooks (Figure 5).

4.3.3 On the starboard side, seven strakes of outer planking, including the garboard strake,survive. As this side was covered by sediment on the seabed, the planks are well

preserved and still show signs of a protective surface covering. On the portside, six

heavily eroded strakes from the garboard upward survive.

4.3.4 The total dimensions ofPiece 4 are 6m x 2.4m. With the original hull curvaturepreserved, the bow section forms the ideal basis for a reconstruction of the vessel. It

is very seldom that this part of a ship is found and can be studied archaeologically.Comparable bow sections or parts of bow sections dating to the 16

thcentury have

only been found on the wreck of a Basque whaler in Canada (Grenier, 1996), and in2004 probably on the wreck site of the Mary Rose (The Mary Rose Trust, 2004).

4.3.5 When still on the seabed, the original Piece 3 broke into two pieces, termed Piece 3aand Piece 3b. Piece 3a formed the eastern side of Piece 3. It consists of fivecomplete strakes and one very eroded strake of lower hull outer planking. On the

inside, only the upper ends of the floor timbers survive. Floor timbers are joined to

first futtocks by an interlocking mortise and tenon joint. The 11 preserved futtocksare broken around the centre, where Piece 3a joins to Piece 3b. Filling frames are

inserted between floor timbers and futtocks, presumably to strengthen the turn of thebilge. Two ceiling planks survive on the inside of Piece 3a. The remainder of the

ceiling planking was lost, when Piece 3 broke apart. Piece 3a is 8.2m long x 2.23mwide (Figure 6-7).

4.3.6 Piece 3b was joined to Piece 3a and represents the remainder of the ships side from

just above the turn of the bilge to the level of the gunports on the orlop deck. Itmeasures 6.3m x 3m.The piece consists of 4 strakes of outer planking leading up to

the main wale arrangement, which is composed of five strakes. One whole gunport

and the edge of a second gunport are visible above the wale (Figure 8-9).

4.3.7 On the inside, the eroded remains of the orlop deck construction can be seen below

the gunport. Deck beams and planks are missing, but a half beam clamp, as well as

part of the waterway and the deck clamp survive. A stringer provides longitudinalstrength on the height of the orlop deck. Comparable 16

thcentury deck arrangements

have previously only be studied in the Mary Rose built in 1510 (The Mary RoseTrust, 2004), the Lomellina wrecked in 1516 (Guerout, 2002) and the San Juan

wrecked 1565 (Grenier, 1996).

4.3.8 Piece 3a and 3b could be joined together, to form one whole run of the vessels sidefrom above the keel to the orlop deck. In the CAD software, it was possible to join

Piece 1 and Piece 2, which were recovered in 2003, to Piece 3a and Piece 3b.


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Altogether, the original ships side is preserved from an area just aft of the bow to

amidships or slightly aft of amidships. Without further research, structuralconnection between Piece 4 and the rest of the ship remains unclear (Figure 10).

5 CONCLUSIONS

5.1.1 The recovered timber structures, as well as the artefactual evidence support theprevious interpretation of the site. The Princes Channel wreck is the remains of a 16

th

century armed merchantman, built from English oak in, or just after 1574 (WessexArchaeology, 2004a). The origin of the timbers used in construction is most likely to

be Essex or East Anglia.

5.1.2 The vessel was carvel built in the frame first method. Certain elements in itsconstruction, such as interlocked floor timbers and first futtocks and iron nail

fastenings in plank butt ends suggest a Mediterranean or Iberian influence. However,

a detailed hull study will be necessary to investigate these aspects more closely.

5.1.3 The nature of the recovered timber structures suggests a keel length of 20m to 30m

for the vessel and a possible overall length of around 35m. More specific statementsabout tonnage and dimensions of the ship will only be possible after a detailed study

of the hull remains. A number of English merchantmen, depicted in a manuscript,

believed to have been authored by the shipwright Matthew Baker in the 1570s(Baker, ca. 1570 1630, Barker, 1986), are the closet representation of the Princes

Channel ships original appearance (Figure 14).

5.1.4 The vessel was probably three-masted, although no elements of rigging have beenfound. The lowest deck in the ship, the orlop, served as a gundeck. Two gunports are

visible in the recovered hull structure above the main wale. A total number of six toeight gunports per side can be assumed.

5.1.5 The ship was possibly outbound from London or another harbour on the Thames or

Medway with a cargo of iron bars, lead ingots and tin ingots. The lead ingots arepossibly from Derbyshire (pers. Comm. Paul Craddock, British Museum). Scientific

metalurgic analysis may be able to confirm an English origin from the trace

elements. The origin of the tin ingots is unclear as yet.

5.1.6 The cause of shipwreck is unknown. The Thames with its many sandbanks hasalways been difficult to navigate, and even though the use of pilots was common in

the 16th century, many ships ran aground with loss of all lives (Harris, 1969,p.119ff.). Apart from a small graving piece repair on one of the earlier recovered

sections, there are no indications of major un-seaworthiness or damage to the outerhull in the recovered wreck sections.

5.1.7 According to a report from 1846, a diver from Whitstable salvaged an ancient

vessel on the Girdler Sands in spring of that year. Among the items lifted from thewreck were: some iron guns, of very ancient date, also some of those curious ingots

and some iron, lead in pigs, red lead in cast-iron casks (Anonymous, 1846). The

location of the described wreck, as well as the nature of the recovered materialsuggests that this wreck might have been the Princes Channel vessel.


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6 FURTHER WORK

6.1 Site

6.1.1 The excavation of the Princes Channel wreck concentrated on the core of the wreck

site and the main aim was to lift the timber structures and artefacts in this area.Although circular seabed searches were conducted to a distance of 30m around the

wreck in situ, not all of this area was airlifted and fully excavated.

6.1.2 The wider surroundings of the wreck site (side scan targets were marked in a distanceof up to 70m from the wreck) could not be examined in the course of Phase III. The

presence of further archaeological material beneath the seafloor cannot be excluded.

6.1.3 It would be advisable to conduct a magnetometer and /or parametric sonar/ subbottom profiler survey before the dredging work starts and have any remaining

anomalies examined by archaeological divers. Provision should be made for

archaeological review of the surveys. In addition, the dredged material should bechecked for small finds.

6.2 Recovered Assemblage

6.2.1 The material investigated in Phases I III is of sufficient importance to progress toPhases IV-VII as outlined in the Project Design:


Phase V: Analysis

Phase VI: Treatment of timbers/ artefacts


6.2.2 The recovered timber structures and the artefact assemblage offer a unique

opportunity to study Elizabethan shipbuilding techniques and ship design. It isbelieved that no other English shipwreck dating to the last quarter of the 16

thcentury,

offers the same amount of surviving coherent timber structure or a range of cargomaterials which can provide important insights into Elizabethan foreign trade

(Alderney Maritime Centre, 2004 and Adams, 1985). As a consequence, the researchframework outlined in the Project Design should be revisited and revised to establish

parameters for further analysis of the timbers and recovered material.


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REFERENCES

Adams, J. (1985). Sea Venture: A second interim report- part I.International Journal of

Nautical Archaeology, 14(4), 275-299.

Alderney Maritime Centre (2004).Elizabethan Shipwreck Project. Retrieved November 10,

2004, from http://www.wreckshed.com/pages/1/index.htm

Alves, F. J. S. (2001).Proceedings: International Symposium on Archaeology of Medieval

and Modern Ships of Iberian-Atlantic Tradition : hull remains, manuscripts and ethnographic

sources. Lisboa: Metropolitano de Lisboa.

Alves, F. & Rodrigues, P. e. a. (2001). Ria de Aveiro A: a shipwreck from Portugal dating to

the mid-15th century; a preliminary report.International Journal of Nautical Archaeology,30(1), 12-36.

Andrews, K. R. (1964).Elizabethan privateering: English privateering during the Spanish

War. Cambridge: Univ. Press.

Anonymous (1846). Proceedings of the Association, December 9th.Journal of the BritishArchaeological Association, 2, 361-362.

Baker, M. (ca. 1570 - 1630).Fragments of Ancient English Shipwrightry, Manuscript.

Cambridge: Magdalene College Library, Pepys 2820.

Barker, R. (1986). Fragments from the Pepysian Library.Revista da Universidade de

Coimbra,XXXII, 161-178.

Castro, F. (2003). The Pepper Wreck, an early 17th century Portugese Indiaman at the mouth

of the Tagus River, Portugal.International Journal of Nautical Archaeology, 32.1(1), 6-23.

Cleere, H. & Crosley, D. (1985). The iron industry of the Weald. Leicester: Leicester Univ.

Press.

Davis, R. (1985).English overseas trade, 1500-1700. Houndmills: Macmillan.

Dietz, B. (1972). The Port and trade of early Elizabethan London: documents. Leicester:

London Record Society.

Fernandez, M. (1616).Livro de Tracas de Carpintaria. Lisbon.

Friel, I. (1995). The good ship: ships, shipbuilding and technology in England 1200-1520.London: British Museum Press.

Gardiner, R. & Unger, R. W. (1994). Cogs, caravels and galleons: the sailing ship 1000 -

1650. London: Conway Maritime Press.

Glasgow, T. J. & Salisbury W., (1966). Elizabethan Ships pictured on the Smerwick Map,

1580. Mariners Mirror, 52, 157-165.


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Grenier, R. (1996). Basque Whalers in the New World: The Red Bay Wrecks. In G. F. Bass

(Ed.), Ships and Shipwrecks of the Americas (69-84). London: Thames & Hudson.

Guerout, M. (2002).La Lomellina. Retrieved November 09, 2004, from

http://www.archeonavale.org/lomellina/

Harris, G. G. (1969). The Trinity House of Deptford 1514-1660. London: Athlone Press,University of London.

Howard, F. (1979). Sailing ships of war, 1400 - 1860. Greenwich: Conway Maritime Press.

Keith, D. H. (1996). Shipwrecks of the Explorers. In G. F. Bass (Ed.), Ships and Shipwrecks

of the Americas (45-68). London: Thames & Hudson.

Kennard, A. N. (1986). Gunfounding and gunfounders: a directory of cannon founders fromearliest times to 1850. London, New York: Arms and Armour Press.

Lavanha, J. B. (1610).Livro Primeiro de Architectura Naval. Lisbon.

Lovegrove, H. (1964). Remains of two old vessels found at Rye, Sussex. Mariners Mirror,50(2), 115-122.

Luz Alfonso, S., D'intino, R. & Soromenho, M. (1998).Nossa Senhora dos Martires.The Last

Voyage. Lisbon.

Nayling, N. (2004). Tree-ring analysis of framing timbers from the Princes Channel Wreck,

Thames Estuary (Dendrochronology Report 2004/02). Lampeter: University of Wales, HARP.

Nelson, A. (2001). The Tudor navy: the ships, men and organisation 1485 - 1603 . London:

Conway Maritime Press.

Oliveira, F. (1580). O Liuro da Fabrica de Naos. Lisbon.

Redknap, M. (1984). The Cattewater wreck: the investigation of an armed vessel of the earlysixteenth century (131). Oxford, England: Oxbow Books.

Redknap, M. (Ed.) (1997).Artefacts from wrecks dated assemblages from the Late Middle

Ages to the industrial revolution. Oxford Oxbow.

Rodger, N. A. M. (1998-). The safeguard of the sea: a naval history of Britain, 660-1649.New York: W.W. Norton.

Roth, R. (1995). The reporting of ordnance: the guns from the Mauritius, a casebook study. In

M. Bound (Ed.), The Archaeology of Ships of War(120-130). Oswestry: Anthony Nelson.

Steffy, R. (1994). Wooden Shipbuilding and the Interpretation of Shipwrecks. College Station:

Texas A&M University Press.

Teesdale, E. B. (1991). Gunfounding in the Weald in the sixteenth century (2). London: Royal

Armouries.


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The Mary Rose Trust (2004). The Mary Rose: 2004 Diving Season. Retrieved November 10,2004, from http://www.maryrose.org/

Thomsen, M. H. (2000). The Studland Bay wreck, Dorset, UK: hull analysis. The

international journal of nautical archaeology, 29(1), 69-85.

Watson, K. & Gale, A. (1990). Site evaluation for marine sites and monuments records: the

Yarmouth Roads Wreck investigations.International Journal of Nautical Archaeology,19.3(3), 183-192.

Watts, G. P. (1993). The Western Ledge Reef wreck: a preliminary report on investigation ofthe remains of a 16th century shipwreck in Bermuda.International Journal of Nautical

Archaeology, 22.2(2), 103-124.

Wessex Archaeology (2003).Princes Channel Wreck, Thames Estuary: Remedial

Archaeological Recording(Ref: 54135.01). Salisbury: The Trust for Wessex Archaeology.

Wessex Archaeology (2004a).Princes Channel Wreck, Thames Estuary: Evaluation Work:

Dendrochronological Dating, Geophysical Survey and Diving Inspection (56472.02).

Salisbury: The Trust for Wessex Archaeology.

Wessex Archaeology (2004b).Princes Channel Wreck, Thames Estuary: Report of

Archaeological Work(Ref: 55011.02). Salisbury: The Trust for Wessex Archaeology.

Willan, T. S. (1938). The English Coasting trade 1600-1750. Manchester: Univ. Pr.

Willan, T. S. (1968). Studies in Elizabethan foreign trade. New York: Kelley.


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APPENDIX I: MITIGATION STRATEGY PROJECT DESIGN


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DRAFT

PROJECT DESIGN

Prepared on behalf of:

Port of London Authority

Bakers Hall

7 Harp Lane

London EC3R 6LB

By:

Wessex Archaeology

Portway House

Old Sarum Park

Salisbury SP4 6EB

August 2004

Ref: 57330

copyright The Trust for Wessex Archaeology Limited 2004, all rights reserved

The Trust for Wessex Archaeology Limited Registered Charity No. 287786


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DRAFT

PROJECT DESIGN

REF: 57330

1. INTRODUCTION

1.1. BACKGROUND

1.1.1. Wessex Archaeology (WA) has been commissioned by the Port of London Authorityto mitigate the impacts of dredging operations on an Elizabethan shipwreck located

within the Princes Channel. The dredging operations will remove approximately 2mof sediment in the Channel and from the nearby Shivering Sands to enable large

shipping traffic to utilise the Thames Estuarys southern approaches to the Port of

London.

1.1.2. This document comprises a Project Design for the excavation, recording and

recovery of the wreck.

1.1.3. This Project Design has been informed by the following documents:

Charter on the protection and Management of Underwater Cultural Heritage ,ratified at the 11

thICOMOS General Assembly, held in Sofia, Bulgaria, 5-9

October 1996;

Standard and Guidance for Archaeological Excavation, Institute of FieldArchaeologists 1999;

Management of Archaeological Projects (MAP2) (English Heritage 1991),notably Appendix II;

An Archaeological Research Framework for the Greater Thames Estuary(Williams and Brown 1999);

Standards and practices in archaeological fieldwork in London, in GreaterLondon Advisory Service Archaeological Guidance Papers;

Guidelines for the preparation of excavation archives for long term storage,United Kingdom Institute for Conservation (UKIC) 1990;


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Waterlogged Wood: Guidelines on the recording, sampling, conservation andcuration of waterlogged wood, English Heritage;

Archaeometallurgy, Centre for Archaeology Guidelines, English Heritage;

Environmental Archaeology: A guide to the theory and practice of methods, fromsampling and recovery to post-excavation, Centre for Archaeology Guidelines,

English Heritage.

2. OUTLINE OF PREVIOUS FIELDWORK

2.1. The Princes Channel wreck was discovered during a pre-dredging magnetometersurvey in April 2003. An inspection carried out by the Port of London Authority

(PLA) Marine Services dive team on 28 May 2003 identified a wooden shipwreck and

steel objects. On 18 June 2003 some iron bars were recovered and an attempt wasmade to disperse the site, but proved unsuccessful. Subsequently, the grab bargeCherry Sand carried out wreck removal operations on 12 July 2003. The recoveredmaterial included a large amount of timbers, iron bars, an anchor and a cannon. A

diving inspection by the PLA at the end of removal operations suggested that the

seabed was clear of obstructions. Navigational dredging operations that wereunderway in Princes Channel at the time had been excluded from the area of the wreck

to avoid damage to dredging equipment. As the seabed appeared to be clear, theexclusion zone was removed and trailer suction dredging occurred in the vicinity.

2.1. Wessex Archaeology was contacted by PLA on 14 July 2003. A brief inspection was

carried out of the recovered material, which noted a possible second cannon amongthe iron debris. As a result, WA was commissioned to carry out remedial recording of

the timbers and iron artefacts, which took place on 14-15 August 2003 (WessexArchaeology 2003). The timbers were interpreted as being from a vessel of up to 200t

burden, with a construction date between 1600 and 1850. The two cannons were dated

to the early 16th

century and to the 18th

century.

2.2. At this point the PLA believed that the wreck had been completely recovered or

dispersed. However, when the PLA survey vessel Verifier carried out a monitoring

survey of the dredged channel on 28 October 2003, topographic high spots were notedabout 30m from the original obstruction. A diver inspection confirmed the existence

of another piece of wooden wreckage. As a result of this discovery, WessexArchaeology was commissioned to carry out a diver inspection of the wreckage on 6

November 2003. The WA divers observed a piece of hull structure, measuringapproximately 6.5m by 3m.

2.3. A side scan sonar survey undertaken on the same day showed the piece of hull

structure, but also further wreckage to the west that probably represented the original

site.

2.4. As the newly discovered section of hull structure was believed to pose a hazard to

navigation, the decision was made to recover it. The lifting operation was carried out

on 20 November 2003 by PLA staff with Wessex Archaeology in attendance. The hullstructure, which came apart in the course of being recovered (Piece One and Piece

Two), was stored at Denton Wharf, Gravesend.


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2.5. On 3 December 2003 a Wessex Archaeology dive team conducted a diving inspectionof the original wreck site. Two separate sections of ship structure were observed on

the seabed. One of the sections was covered in iron artefacts (bars). A fragment of a

Spanish olive jar was recovered during the dives.

2.6. The two recovered pieces of hull structure, Piece One and Piece Two, were recordedby Wessex Archaeology between 19 and 23 January 2004. Elements of the

construction observed during the recording process suggested a date of building in the16

thcentury and a possible Iberian influence upon the construction (Wessex

Archaeology 2004).

2.7. The recovered assemblage consists of some 136 timbers, irons bars, an anchor withwooden stock, a fragment of Spanish Olive jar, a 16

thcentury wrought-iron cannon

and a 18th

century cast-iron cannon. The assemblage still allowed severalinterpretations of the wreck. For example, the span in date range of the cannon could

be explained by:

a late 18th

century or early 19th

century craft carrying the 16th

century cannon asscrap iron;

a 16th

century wreck, with the 18th

century gun being a item possibly lostoverboard from a later craft, or a relic of later salvage operations;

a 16th

century wreck with an 18thearly 19

thcentury wreck in very close

proximity.

2.8. To add to the possible interpretations, the documentary references to shipping losses

in the vicinity include three vessels carrying cargoes of iron dating from the 16th toearly 19th

centuries. At visit to the PRO, Kew, was undertaken to assess the

availability of late 16th

century contemporary historical sources to shed light on theidentity of the vessel detailed in NMR Ref TR18SE 12. At present time, the wreck

remains unidentified.

2.9. As a consequence of the enigmas still surrounding the wreck and to provide a firmbasis for the development of the mitigation strategy, the scientific or absolute dating of

the timbers and the further characterisation of the material remaining on the seabedwere necessary to complete the evaluation phase. WA proposed a project with three

elements to address these matters:

dendrochronological dating, undertaken on 6 May 2004;

geophysical survey, undertaken on 25 May 2004;

diving inspection, undertaken 14 16 June 2004.

2.10 Dendrochronology indicates the date of construction to be shortly after 1574 AD, and

the source of the timber to by Eastern England Essex/East Anglia.

2.11 From the geophysics survey and diving inspection, the overall character of the

material remaining on the seabed can be summarised as follows;


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Area and distribution of surviving

ship structure

Two principal elements Piece Three (6.5m

x 5.6m) and Four (5.6 x 3m) - plus debris

trail and outlying material associated withPiece One/Two up to C. 35m east, possibly

outlying material 15-12, to south west, andanother anomalies up to 50m distant.

Depth and character of stratigraphy: Principal structural elements embedded inbasal hard grey clay to 20-30cm, with thin

layer of fine sands over, No evidence of deepstratified deposits.

Volume and quality of artefacturalevidence:

Ferrous concretion, folded iron bars, ballaststones, lead strip and possible lead pipe all

observed. A fragment of pottery has beenrecovered. Bricks have been noted by PLA

divers. More modern debris has also been

reported. Overall volume not thought to begreat, but as contemporary, relatively closed

assemblage it may be important.

3. OVERVIEW OF INVESTIGATIVE APPROACH

3.1. The mitigation of impacts for the Princes Channel Wreck site is being approached ina series of phases. Phase I relates to remedial recording of loose timbers, sections ofrecovered hull structure and artefacts recovered in 2003. Phase II relates to a

programme of scientific dating, geophysical survey and diving inspection undertaken

in 2004.

Project Phase: WA Project Number/Report Reference:

Phase I: Remedial Recording 54135, 55011

Phase II: Evaluation 56472 (report includes projects 56470

and 56471)

Phase III: Excavation and Recovery 57330


Phase V: Analysis

Phase VI: Treatment of timbers/artefacts


Phase VIII: Archiving


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3.2. This project design relates to Phase III for which WA has been commissioned by thePLA.

4. AIM AND OBJECTIVES

4.1. The aim of this project is to mitigate the impacts of dredging activity on the wreck

site.

4.2. The objectives of the Phase III are to;

Draft and implement a project design and undertake liaison with curators.

Prepare and implement a diver tracking and recording system;

Prepare first-aid conservation provision for finds;

Complete a baseline survey of the material remaining on the seabed;

Excavate and recover dis-articulated/dispersed timbers/artefacts;

Excavate and recover wreck deposits, environmental samples, and largestructural fragments (Piece Three and Four);

At a secure shore side facility, record individual timbers and timber structuresusing conventional methods (hand tape, camera and recording sheets) and 3D

digital survey methods;

Collate, process, check and cross-reference the digital and hard copy archive(including diver observations, position fixing, survey measurements, stillimages, video images, drawings, plans, etc.);

Produce an illustrated report of the investigation, including background, aimsand objectives, methods, factual results of diving and onshore fieldwork, interimconclusion and recommendations.

5. RESEARCH FRAMEWORK

5.1. It is important to recognise that whilst primarily designed to mitigate impacts,

developer-led archaeology is also regarded as research activity with an academic

basis, the aim of which is to add to the sum of human knowledge (English Heritage1996). Curators (i.e. English Heritage) recognise the desirability of incorporating

agreed research priorities as a means of enhancing the credibility of the developmentcontrol process, ensuring cost-effectiveness and legitimately maximising intellectual

return.

5.2. With specific reference to the Princes Channel Wreck, the assemblage has thepotential to add our understanding of many aspects of 16

thcentury maritime life.

Clearly it is unrealistic to attempt to tackle all the possible research themes withinsuch a broad subject area. As a consequence of the above, WA has developed a


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matrix of priorities drawing on the three elements of the Research Frameworksuggested by Olivier (English Heritage 1996).

Resource Assessment a statement of the current state of knowledge and adescription of the archaeological resource.

Research Agenda a list of the gaps in that knowledge, of work that could bedone, and the potential for the resource to answer questions.

Research Strategy a statement setting out priorities and method.

5.3. The assistance of the academic liaison group (see Section 12) has been enlisted tofocus information gathering to address only key questions and define the rationale for

this partial process.

5.4. In forming the matrix below, WA has endeavoured to encourage and assist researchers

to take forward their own research agendas.

Research Category Research Assessment Research Agenda Research Strategy

Build: The vessel remains consists of part of the side from amidships

forward. There appears to be an

Iberian influence on the carvelconstruction, but built the craft

is built of oak from eastern

England. Dimensions indicativeof a large vessel (30-40m).

Exploring shipbuildingtraditions from a period in

history where little documentary

evidence survives. With special

reference to construction

methods, sequence of

construction, the source of rawmaterials and their conversion

into elements of the whole.

To gain insights into theorganisation of ship

maintenance and repair from the

perspectives of what waspossible day-to-day on board

ship and what may be evidence

of repairs conducted at multipleshipyards.

Priority:

To gain insights into sources of

construction materials, methods

of timber conversion, hullconstruction and repair

techniques.

Method:

Conventional and 3D recording

of individual timbers and hull

structure.

Use: The iron bars are thought to be

part of cargo, hence the wreck is

considered to be of an (armed)

merchant vessel. Documentarysources suggest the recovery of

lead and tin, with some of theingots featuring the Royal mark.

Known sources of imported iron

from the Tudor period include

Spain and Sweden (reference

supply to armouries at

Greenwich). Alternatively, blastfurnace smelting was introduced

to Britain around 1500AD.

Hence if the iron bars wereBritish in origin, they would be

early examples of this

technique.

The only evidence of shipboard

To gain a greater understanding

of role of the Thames Estuary as

a conduit for ideas and material

culture, through the linksbetween maritime communities

suggested the assemblage.


of trade routes between the

Thames to the wider world

during a period particularly

noted for voyages of exploration

to the New World.


of early cast-iron working

through artefact studiesassociated of ships cargo.

Developing our understandingof 16th century shipboard life

Priority:

To gather data relating to the

character and nature of theships cargo and artefacts

relating to shipboard life.

Method:

Artefact retrieval and analysis.


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life comes from a fragment of

Spanish olive jar.

from the merchant perspective,

rather than that of ships of war.

Loss: Although the vessel features

various repairs and may havebeen of some considerable age,

the most likely cause of loss

would appear foundering after agrounding incident.

Gain a better understanding of

the effectiveness of the repairtechniques used by 16th century

shipbuilders

Explore the aids to 16th centurynavigation and the role of pilots

in the Thames Estuary.

Priority:

To gain a better understanding

of the circumstances of loss ofthis particular vessel.

Method:

Analysis of evidence of repairs

to the hull.

Documentary research toidentify the wrecking incident

and most common causes of loss

of other vessels in the samevicinity.

Condition: The initial video footage of the

wreck (PLA) and degradation ofthe timber ends noted during

remedial recording suggests that

the site has lain exposed on theseabed and has since been

impacted by attempts at

dispersal.

If vessel is indeed the craft

listed by the NMR (TR18SE12)

frequent salvage and recoveryoperations are noted as having

been carried on over many

years. The main source ofinformation referenced by the

NMR appeared in 1835, and it is

noted the Deane bothers and

Auguste Siebe began patentingtheir designs for diving helmets

in the 1820-30s.

Gain insights into early

maritime salvage operations andhistorical diving technology.

Priority:

Explore the impact of the earlierand most recent salvage

attempts to unravel the

processes of the sitesformation.

Assess the impact of other

processes such as trawling.

Method:

Recording spatial relationships

of dislocated sections of hulland damage to timbers.

Survival: The nature of the underlying

clay and covering sandy

deposits appears to havecontributed to a very high

degree of preservation.


environmental factors that have

contributed to sitespreservation, and explore where

these factors may also be

present elsewhere in the estuary.

Priority:


environmental factors that have

contributed to sites

preservation.

Method:

Environmental sampling.

Investigation: Whilst the science for long-termconservation of large timber

structures remains fraughtdifficulty, detailed recording

remains the only secure way to

capture the information that thePrinces Channel Wreck

assemblage contains.

The Phase I RemedialRecording projects have utilised

conventional and digitalrecording methods.

Improving underwater and dry-land recording methodologies

for development-ledarchaeology to define the most

time and cost effective.

Priority:

Assess the use of conventional

and 3D digital recordingmethods in terms of their ability

to produce the most complete or

comprehensive record.

Method:

Conventional recording and use

of Total Station.


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6. PHASE III METHODOLOGY

6.1. INTRODUCTION

6.1.1. Phase III will be undertaken in four stages;

Diving fieldwork;

Onshore recording;

Post Processing and Archive Collation;

Reporting

6.2. LEVELS OF RECORDING

6.2.1. In its work in various intertidal and marine contexts, Wessex Archaeology hasdeveloped a scheme of Recording Levels comparable with Recording Historic

Buildings: a descriptive specification (RCHME 1996). Wessex Archaeologys

scheme provides for five levels of recording, each with different objectives. It isproposed to adopt level 4 as follows:

Level Type Objective Sub-

level

Character Scope

4 Recovery A record sufficient to

enable analytical

reconstruction and/or

reinterpretation of the

site, its components and

its matrix.

A complete record of all

elements of the site in the

course of dismantling

and/or excavation.

6.3. R ECORDING SYSTEM

6.3.1. WAs Recording System is context based. A running matrix of assigned contexts willbe maintained throughout fieldwork. WA will utilise its standard paper system and

its context, finds and environmental sampling databases to control allocation of

unique IDs for each context, find and sample. WAs recording system has beensupplemented by a digital timber recording form based on published conventions(Museum of London 1990; Steffy 1994; English Heritage 1994) and incorporating

controlled terminology from MIDAS/Inscription thesauri.

6.3.2. An acoustic diver tracking system Sonardyne Scout will be used to provide diver

positioning. Scout is an ultra short baseline system developed specifically forshallow water applications. The diver position can be displayed over geo-referenced

geophysical data, such as side scan images, so the divers can be directed topreviously identified target positions, The integration of a recording database allows

real-time recording of diver observations.


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6.3.3. The Diver Tracking System will be prepared with downloads of the results ofprevious geophysical surveys. The dataset will include the targets highlighted for

investigation in Phase II (Wessex Archaeology 2004, report ref. 56472). The survey

data will also be used to define sensitive areas/exclusion zones for the mooring of thedive vessel to be passed to the PLA.

Underwater Survey and Recording

6.3.4. An outline site plan will be established and maintained throughout fieldwork. The

outline plan will be related to the matrix of contexts.

6.3.5. A network of site datums will be established covering the extents of Piece Three andFour and the debris field to the east of the wreck. A series of supplementary grids

may be established over concentrations of scattered material.

6.3.6. It is proposed to tag and number all the timbers and visible artefacts prior to

commencement of underwater recording.

6.3.7. Diver observations will used to define contexts, the underwater associations of

contexts to contexts and contexts to objects, and to give an initial assessment of theircharacter and condition.

6.3.8. The datums will be used for the rapid recording of the sections of hull structure insitu

and excavation of sediments. In this way, should any timbers come loose or bedamaged during lifting, their position on the seabed will be known.

6.3.9. The Scout system will be utilised to provide the wider world spatial link to the main

site datums and any outlying archaeological material.

6.4. EXCAVATION AND RECOVERY

Use of the Airlift

6.4.1. A thin veneer of sand overlies the contexts of the main timber structures. It is

anticipated that hand fanning and an airlift will be used to clear this overburden.

Artefact Recovery and Environmental Sampling

6.4.2. The sampling strategies that will be employed reflect the question of what life was

like onboard for 16

th

century seafarers and provide clues to site formation processes.Four types of sample are anticipated as follows;

Samples containing small artefacts and any associated sediments/contexts that maybe recovered at the same time because of their close proximity;

Samples of contexts likely to ecofacts, such as fish bones, insects, plant remains,etc.;

Samples of contexts or sequences of contexts which may allow the burial orsedimentation process of the wreck to be understood;


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Samples capable of revealing the complex microbiological underwaterenvironment responsible for the degradation of organic and in organic materials toprovide a baseline for future monitoring of the timbers.

6.4.3. At present time, because of the short diving opportunity that is available, it is

proposed to recover only items which are likely to be contemporary with the wreckand implement of policy of 100% retention. The presence of objects from different

periods will, however, be noted on context records. This policy will be kept underreview as the excavation proceeds, particularly with regard to bulk finds (e.g. ballast

stones) where a sampling strategy may be implemented.

6.4.4. No apparently contemporary finds will be discarded without the prior approval of theEH Maritime Team, Receiver of Wreck and the PLA.

6.4.5. PLA and WA divers have reported pottery scatters, bricks, iron bars, concreted iron

objects, strips of lead, and a lead pipe. As a consequence of these observations,

advice has been sort from The Conservation Centre, Salisbury, on the appropriatefirst aid treatments for these predicted finds types and materials.

6.4.6. In the event of the discovery of human remains, disturbance will cease immediately

and all subsequent activities in the area will be carried out with due care andattention to decency. A licence will be sought from the Home Office to remove the

remains under the terms of the Burials Act 1857.

6.4.7. Finds will be exposed, lifted, primarily conserved, bagged and boxed in accordancewith guidelines set out in the United Kingdom Institute for ConservationsConservation Guidelines No2; the Museum of Londons Standard for the

Preparation of Finds to be permanently retained by the Museum of London andFirstAid for Underwater Finds (Robinson 1998).

6.4.8. It is noted that materials can be divided into classes in terms of their relative stability,for example;

Classification Material finds Immediate or

Short-term storage solution

Class 1: highlyunstable Dye material,paper, leather,

textiles

Requiring immediate activeconservation by a professional

conservator.

Class 2: fairly

unstable

Concretions, iron Material must be kept wet at all

times in fresh water with PHadjusted to 10-12 with sodium

hydroxide.

Class 3: moderately

stable

Wood, copper,

bronze, lead,

pewter

Material must be kept wet at all

times, and cold storage is required.


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Class 4: long term

stable

Bone, glass, silver,

gold, ceramics

Material to be kept wet and advice to

be sort on desalination

6.4.9. WA will implement passive conservation pending more detailed conservation

strategies being developed for individual items. Highly unstable items will be

transferred immediately after retrieval to The Conservation Centre, Salisbury.Provision has been made for a professional conservator to visit and review the

temporary holding facilities developed on board the diving vessel, at the temporaryproject base at Whitstable Harbour and at WAs Head Office, Salisbury.

6.4.10. At present time, it is difficult to specify the likely percentage of the overall contents

of the hull structure that will be sampled. A high priority will be given to samplinganaerobic deposits where organic materials may be preserved. Sample size will take

into account the frequency at which the material occurs. The sampling strategy will

be kept under close review by WAs Environmental Archaeologist.

Recovery of the Large Structural Sections of Hull Timbers

6.4.11. The recovery of the Piece Three and Piece Four will be undertaken by the Port of

London Authority with WA staff in attendance. Special consideration will be given

to providing additional support to the structures, and to the use of spreaders in thestropping to avoid crushing the structure. It is anticipated the two sections of hull will

be covered to reduce light levels and placed in a partially flooded barge acting as apassive holding tank until recovery to the quayside at Denton for the Onshore

Fieldwork.

7. ONSHORE FIELDWORK

Conventional Recording

7.1. Sketch and scale drawings (at suitable scales, but primarily 1:10) will be used torecord details of the main structures and any loose timbers. An interpretative framing

plan will also be produced.

7.2. Detailed descriptions of each timber will be completed to include its associations toother timbers and method of joinery, toolmarks, etc. These will be added to the initial

observations made underwater and collated via the electronic timber recording formthat is part of the WAs diver recording system.

Total Station Recording

7.3. The baseline survey of the hull sections will be undertaken using a Leica, TCR 705

reflectorless Electronic Distance Measurer (EDM). The survey data will be reviewedand assembled on site using a laptop computer running AutoCAD 14.1 and TheoLt

2.1 software allowing real time drawing

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Princes Channel Wreck - Phase iii

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