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THE LANCET. LONDON: SATURDAY, FEBRUARY 9, 1895

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Page 1: THE LANCET. LONDON: SATURDAY, FEBRUARY 9, 1895

353DEFECTS OF VISION IN THE MERCANTILE MARINE AND RAILWAY SERVICES.

THE LANCET.

LONDON: SATURDAY, FEBRUARY 9, 1895.

ON Friday, Feb. 1st, a large and influential deputation, in-cluding almost all the leading ophthalmic surgeons in GreatBritain, waited upon Mr. BRYCE, the President of the Boardof Trade, to impress upon him the extreme importance ofapplying scientific tests to the eyes of men and officers aboutto join the mercantile marine or the railway services. The

chief points which were emphasised by Mr. MACNAMARA,who introduced the deputation, and by the speakers whofollowed him, were that every man should be tested in

regard to his vision both for form and colour ; that this

examination should be conducted by a responsible person,and, if possible, by an expert ; that the conditions in regardto light and distance should be as uniform as possible ; and,lastly, that the examination should be repeated at statedintervals in order that any deterioration resulting from

disease or from the advance of age might be detected. It

was urged, and rightly urged, that such tests were alreadyin use in the army, navy, and Indian services, and more

especially on the Indian railways, and that no difncultywas experienced in obtaining a sufficient number of com-

petent men without visual defects for those departments.Mr. BRYCE, in reply, whilst acknowledging in a very cour-teous manner the great weight and influence of the deputa-tion, contended that the Board of Trade had shown that

they were already fully alive to the importance of the sub-ject. The Board of Trade, he remarked, possessed onlylimited statutory powers ; but quite recently, in the autumnof last year, a modified and improved method of examinationhad been instituted, by which the eyes of all candidates

for the posts of master mariners and of mates were tested ;beyond that the Board was not empowered to go. It had

no statutory powers in regard to railway officials.This reply, however, does not quite touch the root of

the question. Examinations may be instituted, but the

real question is, Are they carried out in a thoroughly satis-factory manner ? It was, moreover, shown by more than oneof the deputation that no effort is even now made to deter-

mine the refraction of the eyes of the candidates, and that

consequently cases of hypermetropia and of astigmatismmay present themselves with sufficient acuteness of vision

to enable them to pass muster and yet be inadequate, afterthe lapse of a variable period, for the due discharge of

their duties. When we consider that the modern liner not

infrequently cuts the water at the’rate of a mile in threeminutes; that she carries from 300 to 1200 passengers,besides a cargo of the value of many thousands of

pounds; that there are scores of such ships afloat;that, as the late accident has demonstrated, she is liable to

be sunk in less than half an hour by a blow affecting avital part delivered by a comparatively small vessel; and, lastly, that the recognition of any danger ahead in time

to enable it to be averted is dependent upon the keenness of sight and correctness of colour vision of two or three

men on the look-out -when we consider all these pointssurely we are entitled to demand that every possibleprecaution to prevent disaster that knowledge and sciencecan suggest should be exercised, and that no painsshould be spared to debar the entrance into responsiblepositions of men whose defect is often not from anyfault of their own, but a congenital imperfection. It

may be perfectly true, as Mr. BRYCE remarked, that

very few, if any, accidents, the causes of which have

hitherto been the subject of investigation, can be shown tohave resulted from the visual defects of the officers or men

on board our mercantile marine ; but it will be acknow-

ledged by all that where so much life and property are atstake it would be madness to overlook an extremely pro-bable though recently discovered source of danger. The

old adage of "Forewarned, forearmed " may still be borne

in mind, especially as the defects in question afford a reason-able explanation of accidents for the cause of which no

plausible suggestion has been made. That which is true of

the mercantile marine holds, in the same sense, for the

railway service, and two cases reported in our issue of thisweek by Mr. W. M. BEAUMONT show well that the dangerto the public who travel by rail from the visual errors of

railway servants is not imaginary. The possession of normalacuteness of vision and of normal perception of colour isimperative among railway officials no less than among sailorsfor the safety of life and for the protection of property.The contention advanced by Mr. BRYCE that the railway

companies are sufficiently alive to their own interests to

prevent men with defective vision entering their service iswell founded, and it appears that several of the largercompanies have taken the precaution to appoint a com-petent surgeon to examine all candidates for admission to

the service. Yet even in these cases it seems to be

doubtful whether the refraction of each eye is accuratelydetermined. It would do no harm if, as Mr. LEET

suggests in his letter to us, some responsible adviser,some professional head analogous to the Director-Generalof the Medical Departments of the Army and the RoyalNavy, were appointed, whose business it should be to

see that the recommendations and orders of the Board

of Trade on this point are carried out, and to whom all

complaints might be referred. This appointment would notenable the railway companies to shirk their responsibility onthe ground that the State certificate superseded their ownduties, as Mr. BRYCE thought would occur if the tests were

applied by a Government official. It would simply ensurethat the provisions for the safety of the travelling publicwere duly enforced. The frequency with which colour-

blindness occurs in the population generally is known tobe about 3 or 4 per cent. ; but it may be of interest

to state that the number of candidates for masters’ and

mates’ certificates of competency in the British mercantilemarine who failed in the colour test during the fifteen

months ending with August last year-that is, before themore recent and better mode of testing the eyes for thisdefect had come into play-was no less than eighty-one,every one of whom in old days would have been permittedto enter the service without question, but to the manifest

danger of Her Majesty’s subjects. The suggestions of the

deputation that the eyes of all candidates for the mercantile

Page 2: THE LANCET. LONDON: SATURDAY, FEBRUARY 9, 1895

354 THE NEWLY DISCOVERED CONSTITUENT OF THE ATMOSPHERE.

marine service should be tested for keenness of vision and

for colour sense, and that the condition of refraction should

be accurately determined by a competent examiner at

regular intervals, seem to be not only prudent but absolutelynecessary, whilst they present no difficulty that render theiradoption impracticable.

THERE is no longer the least doubt that Lord RAYLBIGH,Sec.R.S., and Professor RAMSAY, F.R.S., have made a most

important discovery, and the most remarkable thing connectedwith it is that the new element (or it may be elements) hasbeen separated, not from any rare earths or other compara-tively unknown source, but from our own familiar friend theair we breathe. "Argon" has thus escaped the notice ofinvestigators for nearly a century, and ita probable existencewas only lately surmised by a physicist when he observed thatthe density of nitrogen expelled from chemical compoundswas about 2 per cent. lighter than atmospheric nitrogen;its actual separation and identification seem, however, tohave been reserved until both chemist and physicistattacked the problem. The former was Lord RAYLEIGH

and the latter Professor WILLIAM RAMSAY, and the resultof their joint labour is a happy instance of the success

which attends the cooperation of those who, though engagedin different but adjoining fields of scientific research, yet labour in concert to unfold the secrets of nature. It is

not possible to enter into the masterly and extremelyinteresting argumentative details of the paper contributed

by Lord RAYLEIGH and Professor RAMSAY, the reading ofwhich by the latter riveted the silent but expectant attentionof the Fellows of the Royal Society and their friends in

the theatre of the London University on Thursday afternoonlast week. Suffice it to say that the history of the progressivestages of the investigation was not the least fascinatingportion of the paper, as were also the clear and lucid

arguments and experimental evidence adduced, which leftthe distinguished audience in little doubt as to whether theelement or constituent separated was really new or old.

We may, therefore, pass at once, in accordance with the plan ’,of the chemical text-books, to a brief account of the history,preparation, and properties of the new element. By way of

preface, however, it is impossible to forget the classic workin the last century of CAVENDISH on the composition of theair, which must appeal once more to the wonder and admira-tion of present-day chemists and physicists, his power ofdiscernment being, in the light of this recent discovery,more clearly evident than ever before, since in his

remarkable paper published in the PhilosophicalTransactions in 1788 he expresses doubt as to whetherthe nitrogen of the air (phlcgisticated air) was in kind

elementary, and he even adduced distinct experimentalevidence-based on the oxidation of nitrogen by means ofthe electric spark and subsequent absorption of nitric

fames-of another constituent in the atmosphere. Thus he

wrote, "If there is any part of phlogisticated air of our

atmosphere which differs from the rest and cannot be

reduced to nitrous acid we may safely conclude that

it is not more than th part of the whole." This

residue was, no doubt, Lord RATLEIGH’S and Professoi

RAMSAY’S argon, which occurs probably to the extent o1

between th and th part of the whole atmosphere.

It was by repeating the Cavendish experiment, with the

facility of appliances which the improvements of a

hundred years have afforded, and by adding successive

quantities of air out of which the nitrogen was eliminatedin the manner indicated, that Lord RAYLEIGH and Pro-

fessor RAMSAY showed that the residue could not be nitrogen,but another body, which they have called "argon." "

Under similar treatment chemically obtained nitrogen yieldedno such residue, except such as could be accounted for ,

by accident or other cause. Argon is best obtained, how-

ever, by first freeing the air, from which carbonic acid andwater have been removed, from oxygen by means of red-hot

copper and then absolbing the nitrogen by means of metallicmagnesium, which, when heated to redness, combines withthe nitrogen, forming an orange-coloured mass of magnesiumnitride. The residual gas after this series of operations-thepassage of the gases being repeated again and again-isargon. In this process, again, chemically derived nitrogenyields no such residue. The density of pure argon is 20;hence its molecular weight in accordance with Avogardro’slaw must be 40. There are reasons for believing that, likemercury, its molecule contains but one atom ; its atomic

weight, 40, is therefore identical with its molecular weight.Argon is soluble to the extent of 4 volumes per 100 volumesof water, so that it is about two and a half times as solubleas nitrogen, and possesses approximately the same degreeof solubility as oxygen, and is accordingly found to occurin increased proportion to nitrogen in rain water. Accordingto Dr. OLSZEWSKI, a well-known authority on the constants ofliquefied gases at low temperatures, argon easily condenses to ’

a colourless liquid at a temperature of -128 6° C. and under apressure of thirty-eight atmospheres. At a lower temperatureargon freezes to a crystalline mass like ice ; at a still lower

temperature it becomes white and opaque. Its freezing pointis -189’6°, its boiling point -187°, and its density as liquidis 1’5. As far as spectroscopic work can decide ProfessorCROOKES concludes that Lord RAYLEIGH and Professor

RAMSAY have added one, if not two, members to the familyof elementary bodies. It appears that argon yields two

distinct spectra, and this would indicate it to be in reality amixture of two gases, which have as yet not been separated.On the other hand, Dr. OLSZEWSKi has shown that argonhas a definite melting point, a definite boiling point, and adefinite critical temperature; and these, as is well known,afford excellent criteria of a pure substance, while there is no

certainty that the exhibition of several spectra is neces-

sarily characteristic of a mixture. Still further light,however, is needed upon this all-important point, and thediscoverers hope to decide the question in the experimentalwork which they promise shortly to undertake. If argonbe a single element, then there is reason to doubt

whether the periodic classification of the elements is

complete-whether, in fact, elements may not exist whichcannot be fitted among those of which it is composed. On

the other hand, if argon be a mixture of two elements theymight find place in the eighth group in Mendeleef’s

classification, one after chlorine and one after bromine., If it be Eupposed that argon belongs to the eighthgroup, then its properties would fit fairly well with the

requirements of the periodic law. For the series which

contains silicon, phosphorus, sulphur, and chlorine

Page 3: THE LANCET. LONDON: SATURDAY, FEBRUARY 9, 1895

355SHOULD MEDICAL MEN DISPENSE ?

might be expected to end with an element of mon-atomicmolecules of no valency-i. e , incapable of forming a com-

pound, or, if forming one, being an octad; and it wouldform a possible transition to potassium with its monovalenceon the other hand. "Sach conceptions are, however, of aspeculative nature, yet they may perhaps be excused if theyin any way lead to experiments which tend to throw morelight on the anomalies of this curious element." Lastly,the extreme indifference or inertness of argon to combine

with other elements, in spite of its solubility in water, is

remarkable. This property has suggested its name, whichis derived from &agr;&ngr;-∈&rgr;&ggr;o&ngr;, the same word being used in theGreek Testament in the familiar passage about "everyidle word." All attempts to combine argon with the bodieswhich commonly exhibit a vigorous affinity for certain

elements have proved utterly abortive. Fluorine, which

lays siege to almost every known body, has, however,not been tried. In this connexion it should be borne I

in mind that it is nitrogen’s very inertness which makesit so powerful an agent in modern high explosives ; it

strongly resents partnership or a tied existence, as does

apparently argon, and longs to exchange the solid conditionfor the gaseous. We are face to face, then, with a mass ofremarkable evidence, brought forward with singular skilland clearness by the discoverers, in favour of the existenceof a new constituent of the atmosphere. It has stood

unflinchingly the minute and exacting investigations of Dr.OLSZEWSKI and Professor CROOKES, and the discoverers

have received the congratulations of the presidents of thelearned societies, so that, regarding the important contribu-tion in the light of a proposition, we may write conclusivelyat its end Q.E.D.That being so, what, we may ask, is the significance

of this newly discovered constituent of the atmosphere ? Does, for instance, its presence affect the phenomenonof respiration or of the assimilation of food material

by plants ? Would not its solubility in water, which

is greater than nitrogen and equal to oxygen, lead

to its transmission through the moist membrane of

the lung, and, if so, what part does it play in the physio-logical processes in man upon which his very existence

depends Does its alternating presence in the air possiblyaccount for the bracing influence of sea and mountain air,and are the benefits of balneo-therapeutics, inter alia, to beascribed to argon Again, is it nitrogen or, after all, argonthat is disengaged from certain warm mineral waters, asthose of Buxton ? All these and other questions of probableimportance will at once occur to our readers when they learnthe existence and the properties of the new atmospheric con-stituent. Who can tell, therefore, that the discovery of argonmay not open a new vista even to the student and practitionerof medicine! It is certain that now the existence and posi-tion of argon have been indicated, as with a new planet orcomet, a host of observers will turn their instruments upon itand many deductions on these and other points are sure to beorthcoming.

IT is pardonable perhaps in the vacation season for ourlay contemporaries to devote their columns to the discussionof a very old question-the propriety of medical men

dispensing their own medicines, The opening of Parliament

will no doubt see the termination of such a discussion longbefore the question is settled to the satisfaction of eitherside. Some good things have been said on both sides,and some very foolish things. The subject is one which admitsof no dogmatic treatment, and one on which every medicalman must be allowed to do that which he deems best in the

circumstances of his particular practice. One of the foolish

arguments is adduced in favour of a medical man writingprescriptions. It is to this effect-that he thereby giveshis patient an opportunity of judging of the propriety of thetreatment, for the patient can then see what the medicines

prescribed are, and by consulting a book on materia medicacan tell whether the medical man is acting rightly; as if

the patient were a detective to watch his medical man sus-

piciously, and capable of judging his treatment by referenceto any old book on medicine that might be at his finger ends.Not very much more serious is the argument from the sug-gestion that medical men often injure their patients bymistakes of dispensing, but that nothing comes of it becauseof their power of filling up certificates of death. The teach-

ing of pharmacy in medical education, though more and

more insisted on, is not so perfect as it should be ; but it

is to medical men that we owe all precautions of thera-

peutics and the wisdom of giving the smallest doses of

drugs that are compatible with their usefulness. Theycannot be free from the responsibility of dispensing theirmost powerful drugs, for they have to do so in all nightpractice and in lonely and remote places. It is essential

that they have this faculty in the interest of their patientsand for their speedy relief. Readiness is a great part of thevalue of any medical man- His ready help was alwaysnigh, "-the ability to act and to relieve without waiting forthe assistance of druggists or nurses or any subordinates.They would deprive the general practitioner of a greatpower of usefulness who would dissociate him from the

manipulation and preparation of drugs. They mightas well, and better, dissociate him from the use

of his splints and pocket-case. One writer in our

contemporary, the Birmingham Daily Mail, says trulythat there are in that city medical men who give their

professional services and supply medicine at the rate of

one penny per week per head ! Would that Birmingham-"the best governed city in Europe" -were alone in thatrespect. Medical men are not entirely to blame for thismean arrangement. It is dictated by the "sweating " viewsof the committees of medical aid associations, medical

clubs, &c. But medical men are not without blame and

must feel that they place the profession in an undignifiedand false position. We are not concerned to defend those

who thus bring medical service into contempt. They havebeen condemned by the general judgment of the professionand the implied judgment of the General Medical Council.But while we demand for the medical practitioner the

right to dispense-that is, full control over the immediateand direct use of drugs-we are quite favourable to the

delegation of the drudgery of dispensing to druggists where-ever this is practicable. In country"places and in poordistricts or practices it is not practicable ; but in other

places and circumstances it is practicable and should be

practised. The neat and careful preparation of medicinesjs of such importance that it may properly be delegated in

Page 4: THE LANCET. LONDON: SATURDAY, FEBRUARY 9, 1895

356 SEWAGE ORGANISMS AND DISEASE.

favourable circumstances to one specially devoted to it. It is

not the fault of medical men that such an arrangement as issaid to obtain at Margate is not in much more extensive use,where medical men-and druggists are under mutual obliga-tion-within reasonable limits of course-the former not to

dispense and the latter not to prescribe. If druggists wouldshow less disposition to prescribe and to make secondaryuses of medical prescriptions, and if they would contrive

better to adapt their charges to the means of patients asmedical men have to do, they would do much to hasten thisdivision of labour. It is no part of this argument to dis-

parage the legitimate business of druggists, which is a

dignified and worthy one ; but we’deny entirely their rightto prescribe. The General Medical Council at every meetingremoves from the Register medical men for allowing un-qualified practitioners to act as if they were qualified. This

is what many druggists do, even in grave cases, often withgrave results ; and it hinders that cooperation and con-

fidence of medical men which we all desiderate.

Annotations." Ne quid nimis."

SEWAGE ORGANISMS AND DISEASE.

IN previous reports 1 presented to the London CountyCouncil Mr. J. Parry Laws, F.I.C., made the importantobservation that the micro-organisms contained in sewer airwere not only less in number than the micro-organisms infresh air in the vicinity at the same time, but that they werealso apparently related to and derived from those of fresh airrather than sewage, while there was no evidence forthcomingthat sewage was able to give off micro-organisms to the airin contact with it. Acting on the instructions of the MainDrainage Committee of the Council this investigation hasbeen extended by Mr. Laws, with the assistance of Dr.

Andrewes, to a study of the organisms existent in

sewage. From a copy of the valuable report which hasrecently been issued, and which contains a careful seriesof well-chosen and laborious experiments, we gather thefollowing materials. The most striking difference in thebacteriology of sewage and sewer air appears to be theabsence of moulds from the latter, while in the formermoulds were found to be a predominant feature. The bacilluscoli communis was found, with one exception, in each

sample of sewage examined, but neither it nor its allies wereever found in sewer air. The bacteria of sewage rapidlyliquefy nutrient gelatine, while organisms possessing this pro-perty were practically absent in sewer air. This evidencewould seem to be conclusive that there is no relationshipbetween the organisms of sewer air and sewage, and thewriters are thereby led to think that some of the ill-effectswhich have been erroneously (?) ascribed to sewer air

may be due to subsoil air derived from soil polluted byconstant infiltration of excremental matter, but suggest thatit is not until the outer margin of the permeated soil hasbecome dry that the air is infected with organisms. In a

search for the typhoid bacillus in sewers, where it might beexpected to be present in large proportion, such as in thedrains of the Eastern Hospital at Homerton, they were suc-cessful in demonstrating the actual presence of the bacillustyphosus ; but in a sample taken about a quarter of a mileaway no single colony developing on culture could be referredto the bacillus of typhoid fever. In the light of this and other

1 THE LANCET, March 24th, 1894.

results it is concluded that sewage, even in the absence ofthe normal micro-organisms which it contains, is clearly anunfavourable medium for the growth of the typhoid germ,whereas the colon bacillus can grow and multiply freely init. It might be anticipated, it is pointed out, that in com.petition with other organisms, able to grow well in sewage,the typhoid bacillus would die out even more speedily.These experiments are only preliminary and are necessarilyincomplete, but they give a distinct indication of the pro-bable fate of typhoid bacilli which gain access in a livingcondition to sewage, while it seems " clear that sewage doesnot form a medium in which much, if any, growth is possiblefor them under natural conditions, and their death is probablyonly a matter of a few days, or at most one or two weeks." Obviously, this resistance to growth may be overcome byattenuation, as when sewage has access to the drinking supplyor to milk. It would appear, then, that so far as bacteriologicalanalysis goes there is no ground for believing that sewerair plays any part in the conveyance of typhoid fever; but arethe conditions under which the bacteriological examinationsof sewage and of sewer air are made such as to give nsabsolute assurance on these and other points ? In spite ofits apparent bacteriological innocuousness no one entertainsthe least doubt that sewer air is a constant source of disease,and if this is not to be referred to micro-organisms towhat may it be ascribed 2 There is undoubtedly a poisonousagency at work when sewer air is inhaled, which, though itmay not directly act, yet so prepares the soil that the systemis unable to resist the invading organism when it comes.In some well-known experiments recorded in THE LANCET 2it was shown that when rats, amongst other animals,were inoculated with a weak growth of typhoid culture, afterpreviously being exposed to sewer emanations, they nearlyall succumbed. On the other hand, rats treated to the samedose of typhoid culture, but exposed to fresh air after inocu-lation, showed little sign of illness and eventually recovered.What, then, is this poisonous constituent of sewer air whichleaves the system defenceless against the attacks of the

microbes which it may encounter ? An investigation on thispoint would form, we suggest, an excellent and fitting sequelto the above valuable contribution.

SNOW SALT, AND SLUSH.

EVERYONE will agree that the severe and bitter cold weare experiencing just now hardly requires accentuating.Eight degrees of frost all day in London, with pro-bably twice that number registered in the suburbs,require no ordinary amount of endurance on the partof pedestrians, but to reduce this to zero by artificialmeans on the pavements of our streets is intolerableand unnecessary. Yet the sprinkling of salt in the streetsappears to be the only means which has occurred to thestreet authorities for removing the fallen snow. It is a

matter of common knowledge that such a mixture producesinstant liquefaction and consequent great absorption of heat,and the temperature of the resulting mixture, pro tempore,sinks to zero. But this is not all ; the mixture, beingsaline, remains wet at a temperature considerably belowfreezing point, so that the pavements are made much moreuncomfortable and cold than they would be if nothing atall was done. There is little doubt also that the salt solution,finding its way into the soles of boots, renders them per-manently damp and therefore permanently cold. The roads

(for we must bear in mind our four-footed friends) and thepavements should be swept immediately after a fall of

snow, or, if salting must be done, the saline slush could be"squeegeed off " the moment it is formed so that we mayhave at least a dry footway. The street sanitary authoritiesshould surely use their powers and, if unable to do the work

2 THE LANCET, Sept. 29th, 1894.


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