70

rapid revolution, into the face of the worker. These particlesare borne into the lungs, and induce a bronchial irritationand cough which partake of the character of a bronchialphthisis. Dr. Cbolmeley has known three persons who havebeen obliged to leave their occupation from this cause.Wig-makers, hair-cleaners, and other workers are affected

in a similar manner, and the unhealthiness of the occupa-tion is very definitely shown by the rate of mortality of theworkers, whicb, from the age of twenty-five onwards, isgreatly above the average.

Dusts containing organic vegetable matter in considerablequantities lead to other mischiefs than irritation. The dustarising from tobacco-leaf during the process of makingcigars is excessively injurious unless the most perfect ven-tilation be secured. The symptoms induced are oppressionof breathing, dryness of the throat, and in young handsgiddiness and nausea.The dust produced from the various processes of snuff-

making is more injurious still. The tobacco leaf, finely- divided, is moistened with lime-water and mixed with salt,sometimes even with floor-dust sweepings, and in yellowsnuff with red lead. During the drying of this mixture, andwhile it is being turned over in the drying, there arises withthe dust a smoke which so affects the younger workmen thatthey become faint and vomit until they are rendered tolerantof the poisonous matter they inhale. In the further processof sifting the snuff,-after it has been ground preparatoryto adding " liquor," namely, salt and water to give weight,and scents to give perfume,-the air is charged again withdust, which produces the same symptoms as those abovedescribed. Thus organic nervous disturbance is another- evil added to the table of disease.The dusts of certain soluble saline substances give rise to

great bronchial irritation. The dust of sulphate of iron usedin fur-dyeing is one of these substances. This dust also actsupon the teeth, destroying the enamel, and adding caries ofthe teeth as an additional malady of industrial origin. Itwas but fair to add that improvements in the processes inwhich this salt is used have led to the removal of dangerswhich at one time were general.The poisonous dusts are mainly those in which the salts of

arsenic are diffused in fine division. In the colouring ofartificial flowers, in some branches of paper-staining, and insome cases where arsenic has been used for preserving pur-poses, as in the preservation of the skins and furs of deadanimals, the dust of arsenical compounds is distributed andinhaled. The arsenical salt, mixing with the secretions ofthe mouth and throat, is swallowed in some instances, andexcites irritation of the stomach and other symptoms ofarsenical poisoning. In one of these examples Dr. Richard-son saw the gastric mischief assume a gastro-enteric type.In all instances there is a continuous dyspepsia so long asthe source of the evil is present. Gastric irritation andacute dyspepsia form, therefore, two further additions in thetrain of industrial pathology.The dusts which are obstructive as well as irritating are

principally those of flour, dried or partially dried clay,lime-dust, fine dust of carbon, coal-dust, carbon scrapings,and rouge. Workmen employed in flour-mills, in earthen-ware manufactories, in mining, in loading and unloadingcoal, in walking-stick making, in jewellers’ work and otherburnishing trades, are subjected to one or other of thesevarieties of dust. All the dusts cause irritation of thebronchial passages, but some also produce direct obstructionto the free passage of air through the minute ramificationsof the bronchial tubes into the air vesicles. Thus an ir-

regular pressure of the inspired air is brought about, anundue pressure is exercised upon a portion of the lungstructure, there is rupture of vesicles and production ofwhat is technically called emphysema. The symptomsattendant on this condition are those of suffocative

breathing and spasmodic cough, ordinarily designatedasthma. In 11 miller’s asthma" this condition is mostdestructive. With the emphysema there is alwaysbronchial irritation and chronic bronchitis, superaddedin a greater or lesser degree of intensity. In coal-minersthe distribution of carbon-dust through the lungs is so ex-tensive that the organs sometimes assume the colour ofcoal, and a condition of disease like to what is known asmelanosis is induced. Thus three other forms of diseaseare added to the schedule of industrial maladies.

After narrating various other facts connected with dust

Dr. Richardson moved to the second subdivision or order ofthe class of injuries from inhalation of foreign substancesby the lungs-namely, from the inhalation of vapours andgases. These agents he placed forward in series-viz.,gases of carbonic oxide, sulphurous acid, hydrochloric acid,and chlorine; vapours of nitric acid, of ammonia, of tur-pentine, of bisulphide of carbon, of aniline, and of nitro-benzine ; fumes from heated resin ; metallic fumes, such asthose rising in smelting metals, and in founding, such asthe fumes of mercury, copper, and zinc.

In various occupations the presence of carbonic oxide inthe atmosphere surrounding the worker is a source ofdanger, and some typical illustrations of this fact were sup-plied. The gas, invisible and inodorous, and evolved freelyduring the apparently simple operation of burning coke orcharcoal in a chafing-dish, is frequently inhaled in closerooms, its presence being unrecognised as a source of thesymptoms it excites. In cold weather women working atthe lace-frame are often led to place a chafing-dish ofburning coke beneath the frame, and directly under theirown nostrils, the object sought being that of keeping thehands warm for the performance of the work, which re-quires delicacy and precision of hand movement. In thisway the women are made to breathe an atmosphere chargedwith carbonic oxide and carbonic acid from which theysuffer severely. The acute symptoms are headache, giddi-ness, nausea, faintness, flushing of the face, and irregularaction of the heart. The chronic symptoms are failure ofappetite, f03 tor of breath, a nervous, hysterical condition, andanaemia, with great depression of muscular power. Men arenot, more than women, exempt from these effects of car-bonic oxide. Dr. Richardson had under his observation abrazier who was affected dangerously from this same cause.The man, who worked in a small, close shop, was accus-tomed to use an open chafing dish of heated charcoal forkeeping his irons hot after they had been raised to rednessin the fire of the forge. In him the symptoms induced werethose of vertigo, and they remained even for a long timeafter he was removed from the influence of the gas. In thecourse of the description of the above-named facts, thelecturer related some experimental inquiries which he hadmade with carbonic oxide, from which it was shown that theinhalation of this gas in free quantities will induce a tem-porary diabetes. It had not as yet been ascertainedwhether diabetes had been excited by this means in thosewho work in an atmosphere containing carbonic oxide ; butit had been observed, in corroboration of the experimentalevidence, that some men exposed by accident to the gaswere diabetic for a period after their recovery from thenarcotic and from other immediately dangerous conditionsinto which they had been cast.The action of sulphurous acid gas was next brought under

consideration. This gas is used largely for bleaching pur-poses ; as, for instance, for bleaching plaited straw, andeven for bleaching corn. Two classes of industrials suffer;they who are occupied in the process of bleaching, and theywho are exposed to the bleached products before the gashas entirely escaped; men who unload bleached oats forexample, such as fellowship porters and the like. The

symptoms caused by the inhalation of sulphurous acidare acute and chronic. The acute symptoms are those ofdifficult breathing and suffocative cough; these are tem-porary in character, and are less hurtful than might beexpected from their frequent severity. The chronic sym-ptoms, produced by long exposure, are feebleness of body,undue fluidity of the blood, biliousness amounting evento jaundice, and anaemia.

PROFESSOR SANDERSON ON THE PROCESSOF INFLAMMATION.

LECTURE I.-PART II.

THERE is a doctrine which has woven itself into the

pathological teaching of the last thirty years, based, indeed,on Hunter’s, but opposed to his observation-viz., that ofincreased action on the part of the tissues-a doctrinewhich is really quite as groundless as that of Hunter. The

doctrine of increased attraction implies and takes for

granted that there is another force in addition to that of

71

the heart concerned in the circulation in the capillaries.This " capillary force " has become historical ; it was thirtyyears ago taught in its entirety by Alison. The phy-siological facts upon which it is based are not easy to grasp.It has no basis in experiment, and doubtless there is notheory for which physiological support may not be found ifthe upholder persisted in not seeing the contra, but re-garded only the pro. It was said, among other things, thatthe capillary circulation in frogs goes on after death, andthat it could only do so by reason of " capillary attraction."But it is now well known that this fact is due to the arteries

after death continuing to undergo rhythmical dilatationand contraction. So also another fact observed in the livinganimal-viz., irregularity in the flow of blood-is due tothe same rhythmical action of the arteries, as may be wellseen in the ear of the rabbit. Again, it was said that withoutcapillary attraction it would be impossible for arteries toempty themselves after death. But the artery emptiesitself by virtue of its own contraction. Asphyxia used tobe said to be due to stagnation in the pulmonary capillaries,which no longer originate vis vioa, and so cannot emptythemselves. But every physiologist knows that in asphyxiathe left heart is invariably full of blood, which would be in-consistent with pulmonary obstruction. The experimentsof John Reid were made to do service in the same cause.

They showed that in asphyxia the arterial pressure wasincreased-an increase attributed to the destruction of

capillary power. Most of these facts were explained bythe discovery of the vaso-motor system of nerves (byBrown-Sequard), by which it followed that the distribu-tion of blood in an organ depended upon such nerves. In

pathology, however, the doctrine still held ground, andcame greatly into favour when, between 1850 and 1860, themicroscope was holding sway. So great an influence hadthe microscope gained, that it was stated in Edinburgh thatthe cellular products of inflammation, of tubercle, and ofcancer, could be differentiated by its means, and in Londonthere was published a work entitled " The Principles of theCure of Disease as shown by the Microscope." At thistime, too, the changes due to inflammation in extra-vasculartissues had been recently described-viz., in cartilage byGoodsir and Redfern, and in the cornea by His. Finally,Virchow, basing his observations on inflammatory changesin bone, muscle, &c., described apparent regions of increasedaction of the tissue, and built thereon his well-known11 cellular theory." Virchow’s docrine is that there occurlocal disturbances of nutrition, extending from masses oftissue or centres, and in 1854 he first gave his reasons foradopting this view in preference to that of Hunter. Thebest exposition of this doctrine-better, indeed, than thatgiven by Virchow himself-is given by Mr. Simon in hisEssay on Inflammation in " Holmes’s System of Surgery,"first edition, 1860. He says :-" A part does not inflamebecause it receives more blood; it receives more bloodbecause it is inflamed. ’Action,’ says John Hunter, createsthe necessity for support, and supplies it.’ How this iseffected need not now be discussed. Simply let it be re-cognised that with the greater necessities of a part all

required blood-supply comes to it, and that the enlarge.ment of bloodvessels which permits this affiux is due not toany mechanism acting a tergo, but to an influence primarilyexerted by the part." He then proceeds to illustratethis distinction by contrasting two cases, in the one ofwhich the femoral artery has been obliterated for aneurism,and in the other in which amputation of the thigh hasbeen performed. "In both cases the main artery is ob-literated, and at about the same spot, in both cases thepressure of the heart’s action is the same ; but in one casethere remains no requirement for blood below the place ofligature, and accordingly the collateral bloodvessels undergono enlargement; whereas, in the other case, the entire re-maining limb requires its customary supply of blood, andthe collateral bloodvessels accordingly enlarge so amplythat not an hour’s ansemia is inflicted on it ......... What is itthen in these cases that opens a way for collateral circula-tion ?........Evidently not increased pressure by the heart,but diminished resistance by the artery." Indeed, the imme-

diate effect of a ligature is to diminish the pressure in thevessel beyond the seat of constriction, so that the bloodpasses under an increased pressure through the collaterals,and with increased velocity,-the rate at which blood flowsalong an artery depending on the difference in pressure atdifferent parts. Applied to that view of inflammation nowunder consideration, it might be stated thus,- that theflow through the collaterals is the result of increased attrac-tion by the tissues ; or, in the words of Dr. Alison : " Itis highly probable that the primary and fundamental

change is not in the vessel itself, but between this and thevital changes in the tissues." It was only towards the endof his life that Alison became aware of Goodsir’s researches,and had he lived to see the acceptance of the "cellularpathology," he would have hailed it as further proof of thetruth of his cherished vis afronte.Accordingly Virchow and his followers believe that tissue

overgrowth is the constant and central fact of inflammation.Mr. Simon, in his description of the microscopic charactersof an inflamed part, dwells upon the textural changes at themargin of the focus of inflammation, and points out theirderivation from the multiplication of textural elements andtheir final destination in pus. According to him the tissueis excited and attracts or draws blood to itself. The stateof physiology at the present day is very different from whatit was tweutv- five years ago, when Alison taught. Now, bymore exact observation and experiment, it has become im-possible for us to hold the doctrine that the heart is inade-quate to carry on the circulation. Alison’s influence wasgreat, but his mode of teaching was not the one calculatedto keep the mind open for the reception of new facts. Healways set forth his conclusion first, and then explained thefacts on which it was based,-a method bad for the studentof nature to pursue, but even worse for the physiologist;for in that way it was easy to fit facts to theories. At thepresent day the physiologist takes a different stand. Theworst accusation that can be made against him is that hehas no view at all. But the theories of the past must bedemolished ; such words as "irritation" must be got rid of-words which in their original meaning assume a property ofirritability, and we must substitute or it the phrase "injuryof tissue." And with regard to many questions it is farbetter to leave the mind open rather than set up somefavourite theory. In pathology our knowledge is still tooimperfect not to need the rational and scientific use ofthe imagination. It is better then not to commit ourselvesto views, baseless i fact, and purely theoretical, whichwe may live to see rejected as untrue.

SIR WILLIAM HARCOURT ON THE HEALTHOF OXFORD.

ON Monday night, at the Druids’ dinner at Oxford, SirW. Harcourt, M.P., spoke at considerable length on thesanitary condition of the city of Oxford. Sir William

Harcourt condemned severely the action of Mr. Cave in

bringing forward last session in Parliament a motion im-

puting to the authorities wilful and culpable neglect of thesanitary condition of the town. This motion was ultimatelywithdrawn in order that Mr. Cave might obtain additionalevidence sufficient to support it. Sir William Harcourt

urged, however, that this evidence ought to have been inMr. Cave’s possession before the motion was pnt down. SirW. Harcourt alluded to the energy with which the extensive

system of drainage was being carried out, and the satis-factory nature of the scheme. He denied that Oxford was,or is now, an unhealthy city, and he based his assertion onthe Registrar-General’s returns for 1872, which assigned toOxford a death-rate of 193 from all diseases, and from thoseof the zymotic class 2’5. In 1873 he admitted that the raterose to 21-9. In 1874 the total number of deaths was 713,to an estimated population of 33,000; but deducting thedeaths of persons brought from the country to the infirmary,the number must be reduced to 691, yielding a death-rateof 20-5. These figures, he concluded, were sufficient torefute the charge that Oxford was an exceptionally unhealthyplace, or that the authorities had neglected their duty. We