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The greatest discrepancy between the actual and the calculated mortality is at the mean elevation of 20-40 feet, and on examination this elevation is found to include the districts of Bethnal Green and Wandsworth, where other disturbing causes combined to heighten the mortality.

We have already seen that the effect of bad water almost disappears under the paramount influence of elevation. We shall now extract a portion of another table, to show that density of population and over-crowding, which exerts some influence over mortality, has also by the side of elevation comparatively little effect:

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The extraordinary effect of elevation appeared so important, that it was thought right to submit the principle to another test, by comparing the elevation and the mortality from cholera of each sub-district. The result entirely confirms the announced law.

This law of elevation is perhaps the most important practical point brought out in the Report, and is well worthy the attention of the authorities of the East India Company; for the fact, though long recognised, has never been so definitely shown before.

(c.) Density of Population.—Contrasted with elevation, density has, little effect; yet when the effect of elevation is eliminated, density is found to have some influence. Thus in the 19 densest districts, where the inhabitants were 178 to an acre, the mortality was 71 in 10,000; whereas in the 19 least dense districts, where there were only 34 inhabitants to an acre, the mortality was 61 in 10,000.

(d.) Wealth and Poverty.—The influence of wealth and poverty cannot be fixed, and appears to be less considerable than was supposed. Elevation, however, interferes so much with the results, that it is unsafe to hazard any conclusions.

(e.) Influence of General Insalubrity of District.—There is a very constant relation between the mortality from ordinary causes, and the density of population. Places generally insalubrious suffered most from cholera. Thus of'the 38 districts into which London is divided, 19 have a density of 155 persons to an acre, a mean elevation of 26 feet, and a mean annual mortality of 268 in 10,000; the mortality from cholera was 84 to 10,000. The 19 other districts have a density of 57 persons to an acre, an elevation of 55 feet, and a mean annual mortality of 212 in 10,000; the mortality from cholera was 48 in 10,000. The facts appear to be, that a low elevation contributes to

feneral insalubrity, as well as to cholera; but that its effect is not so great on other iseases as density of population. Inferences from these Facts.—If we apply these facts, derived from a careful study of the epidemic in London, to the country generally, it is found that the inferences drawn from them hold good everywhere. In every place, elevation exerted a paramount effect; and density of population and poverty were subsidiary influences. It remains, then, carefully to consider in what manner elevation acts.

"As we ascend," says Mr. Farr, " the pressure of the atmosphere diminishes; the temperature decreases, the fall of water increases, the vegetation varies, and successive families of plants and animals appear in different zones of elevation. The waters roll along the surface of the rocks, or filter through them and the porous strata of the earth, to burst out below—the sources of rivere or of tributaries, which carry disintegrated rocks with the remains and excretions of vegetables, animals, or men, in every stage of decomposition. The deposits in stagnant places, and at the estuaries, show the kind and quantity of mixed matter which the laden rivers carry down and deposit on the low margins of the sea at the tidal confluences of the fresh and salt waters

"As the rivers descend, the fall of their beds often grows less, and the water creeps sluggishly along or oozes and meanders through the alluvial soil. The drainage of the towns is difficult on the low ground, and the impurities lie on the surface or filter into the earth. The wells and all the waters are infected. Where the houses are built on hill-sides and elevations, as in London, the sewage of each successive terrace flows through the terrace below it, and the stream widens, the ground becomes more charged, every successive step of the descent, until it is completely saturated in the parts lying below the high-water mark.

"The river, the canals, the docks, ana the soil of a port may be viewed as a large basin full of an almost infinite variety of organic matters, undergoing infusion and distillation at varying temperatures; and as the aqueous vapor which is given oft ascends, it will be impregnated with a quantity of the products of the chemical action going on below, variable in amount, but necessarily greatest in the lowest and foulest parts The amount of organic matter, then,

in the atmosphere we breathe, and in the water, will differ at different elevations, and the law which regulates its distribution will bear some resemblance to the law regulating the mortality from cholera at the various elevations. It has been seen how rapidly in London the mortality from cholera diminishes a few feet above the low ground on a level with the Thames, while several feet of elevation in higher regions produces no sensible effect

"It is established by observation, that cholera is most fatal in the low towns and in the low parts of London, where, from various causes, the greatest quantity of organic matter is in a state of chemical action; and it may be admitted that cholera, varying in intensity with the quantity, is the result of some change in the chemical action of this matter. Further inquiry must determine whether in England that change is spontaneous, or the result of the introduction of a zymotic matter from Deyond the seas; whether the poison enters the human frame in air or water, through the skin, the mucous membrane, or the air-cells of the lungs." (pp. 69-70.)

The readers of our journal need scarcely be reminded how frequently we have advocated views identical with these, and how we have over and over again pointed out, that all observers who have regarded cholera with an unprejudiced eye, from the days of Jameson downwards, have adopted opinions of a similar kind. Let us hope that this reiterated assertion—an assertion based on observations so numerous and so accurate, may at last have some weight with the rulers of this and other countries; and that we may at length commence in good earnest those works of sanitary improvement, the neglect of which is the opprobrium of the present generation, and the fatal legacy which it seems is to be inherited by the next.

Mr. Farr does not allude here to a modus operandi of a humid atmosphere already charged with organic exhalations, which seems to us very important—namely, its effect in causing the retention within the body of various organic excreta, which are given off especially by the lungs, and which require pure air in quantity to oxidize them to the degree requisite for elimination. It is probable that by their accumulation in the system, a predisposition is given to cholera as to so many other diseases; but to this subject we must devote some of our space on a future occasion.

The latter half of Mr. Farr's Report is not so good as the first. He quits his facts and figures, and ventures into the shadowy regions of "theories and analogies." The cause of cholera, whether from volcanic action, electricity, ozone, heat, fungi, bad water, is discussed shortly and imperfectly; then Dr. Snow's views, contagion, and spontaneous development, come in for a few pages. Subsequently, Mr. Farr, with the intention of showing that other zymotic diseases are governed by similar laws to those of cholera, discusses shortly the effect of elevation on ague, yellow fever, and plague. Various other speculations are then brought into view; such as the salubrity and unhealthiness of ancient and modern Rome and of Egypt, sanatory instinct, the effect of healthy places on animals, the effects of the earth on race, the degeneration of race in unhealthy places, <fcc. Many of these topics are handled with skill, and all of them will be read with interest, although they are fragmentary, and, we cannot but think, rather misplaced in the present Report. The latter part of the Report is indeed expanded into a kind of treatise on general hygiene, but it is a sketchy and imperfect treatise.

There are some points, too, on which we cannot agree with Mr. Farr. Thus, he has clearly underrated the great influence of long-continued fatigue, as of long marches by troops, in giving a predisposition to cholera. He says that such long marches only expose troops for a longer time to the causes of the disease. But he has entirely overlooked the cases in which the march has been through a healthy country, and the attack has occurred in cantonments which had become infected subsequently to the entrance of the healthy troops: the way in which the eighty-sixth regiment suffered at Kurrachee is an example of this ;* and many others might be quoted. It is likely, or at any rate very possible, that after long marches and great fatigue, the system is impregnated with the products of the used tissues which have been decomposed with unusual rapidity, and probably, therefore, not so perfectly as to allow their complete oxidation and excretion from the system. Whether this be the case or not, the effect of long marches as a predisposing cause of cholera, is certain.

We will not, however, lessen the pleasure of our task by seeking out points on which we differ from Mr. Farr. We would rather thank him gratefully for his most able and interesting Report. It will always be a work of authority and reference; and in its numerous tables and calculations it contains vast mines of facts, which wc trust that future industrious observers will not be slow to explore. The work is another proof, if such were needed, of the important results to medical science of this registration of deaths. Among the greatest services which have been rendered by the registrar-general, is the light which his researches have thrown on the vital question of hygiene. For what has already been done in this direction, we have in great measure to thank Mr. Farr. We can safely say, that few men have done more good in their generation, and that no physician of this or any other time has been more instrumental in pointing out how the ravages of disease may be checked at the outset most speedily and efficiently.

We have numerous works on cholera before us, to which we hope soon to do justice. Dr. John Taylor's excellent Report on Cholera in Huddersfield; Dr. Bryson's and Dr. Snow's treatises, and almost innumerable German and French works, among which Schmidt's original and important treatise is pre-eminent, will be carefully examined as speedily as may be.

* 8«e British and Foreign Medioo-Chirurgioal Review, vol. ii. p. 86.

Art. V.

Des Vices Congenitaux de Conformation des Articulations. Par Aiph. Robert. On Congential Deformities of the Joints. By A. Robert.Paris, 1851. 8vo, pp. 260. This little work constituted the Thesis presented by M. Robert, during the concours which took place for the chair of Clinical Surgery in the Faculty of Medicine in 1851. It presents a very intelligent summary of what is known upon the subject: but we should have expected that one enjoying so high a reputation, and possessed of so wide a field, as the surgeon of the Beaujon, would have been able to contribute more from his own resources than has been the case. We shall pass the various sections of his work briefly under review.

1. Pathological Anatomy of Congenital Deformities of the Joints.—The anatomical changes are of the most varied kinds, according to the form, degree, and primary cause of the deformity, the articulation that is the subject of it, and the length of time that has elapsed from birth when the parts are examined. As the majority of cases have only been examined in the adult condition, the pathological evolution of the changes consequent on congenital displacements is much less known than it would be, had they been examined in the various stages of such progress. In considering, with this reservation, the condition of the different parts forming the joint, we find that the bones may be absent entirely, or in part, be separated from each other by unnatural intervals, or be abnormally fused together. They may be luxated, and they may become the subjects of organic lesions, as in the adult. In other cases their development is defective or arrested. As a general rule, atrophy is met with in all cases in which the movements of the limb have lost much of their extent. It is one of the best established laws in physiology, that diarthrodial surfaces owe the integrity of their forms and of their nutrition to the pressure they exert on each other in their normal condition; and when this ceases to prevail, the heads of the bones lose their geometrical forms, become rugous, and deprived of their articular cartilages, and even are changed into conical or filiform osseous prolongations, while the cavities become filled up so as to present irregular depressions, or even projections. If the bones have not entirely lost their relations, as in sub-luxations, the osseous surfaces rub against each other in new and abnormal spots, and reciprocally leave traces of wasting which are most seen on the least moveable bone. The cartilages become destroyed, and the surfaces eburnated by this compression and friction, which are among the chief causes of the deformed appearance of the heads and condyles of the bones, and of the formation of the new cavities for the reception of these. When, however, the displaced bone does not come into contact with any osseous surface, it still undergoes change, hollows itself out a receptacle in the muscular parts, and becoming surrounded by these, by ligamentous adhesions, and by an accidental synovial bursa, assumes some resemblance to a normal articulation.

The ligaments and fibrous capsules undergo modifications in form, length, and structure. At first, abnormal laxity of the ligaments is often the only change which the joints present. They are thinner and more distended, but their insertions into the bones have continued normal, their direction only being changed by the displacement of the articular surfaces. This relaxation continues to increase with the progress of the affection; but as fibrous structures yield very slowly to traction, they long strive against the displacements which muscular traction and the action of gravity are constantly tending to produce. In the deviations or sub-luxations of ginglymoid joints, while some of the ligaments are distended, those opposed to them become shortened, sometimes with and sometimes without an accompanying interstitial hypertrophy. The synovial membranes follow the displacement of the capsules, and may secrete more abundantly than in the normal condition.

The alterations in the muscles play an important part, these being both numerous and varied, and capable of arrangement under various heads, accordingly as they affect the form, size, direction, or texture of these parts. When certain portions of the skeleton are wanting, the muscles that should be inserted into these may be also absent; and, in congenital anchylosis, many of the muscles fitted for moving the bony levers now confounded together, may be wanting—these last cases being, however, rare. Alterations in the length of muscles, in congenital deviations and dislocations, are far more common; such modifications being usually accompanied by changes in their direction.

"Consequences of the highest interest flow from the facts we have mentioned: 1. Changes in the direction of muscles, the increase or the diminution of the angle that their insertions form with the bony levers, may entirely change their physiological action. Thus, in very marked deviations of a limb, we may observe the flexors becoming extensors, and reciprocally; this depending upon the displacement they have undergone. M. Bouvier has related to us the case of an individual, the subject of extreme flexion of the knees, in whom the triceps femoris, at first tense, had luxated the patella outwardly, and had then slid over the external surface of the condyle so as to become a flexor of the leg upon the thigh.—2. The deviation of a limb, by rendering the insertion of a muscle more favourable for motion, multiplies its action, and causes it to predominate over that of its antagonist, in spite of the hypertrophied condition which the latter often presents. This fact is observed in club-foot.—3. Finally, it results from the property of tonicity, that when a muscle, the points of attachment of which have become approximated, has remained long in this position and become accommodated to it, it will become really shorter, and will oppose an energetic obstacle to the rectification of the deformity." (p. 16.)

The muscles in a great number of instances, and especially in the congenital deformities of new-born infants, are in the possession of all their'structural and functional properties; but this is not always the case, for in other cases their structure may Undergo change or their contractility may be lost. In some few cases the whole or part of a muscle may become hypertrophied, being thick, red, and larger than in the normal state; but in general it is found in quite an opposite state, flaccid, and less coloured. It may be in different degrees penetrated by adipose tissue, to the extent of almost entirely transforming it into fat. In other cases the red portion of the muscle may disappear without being replaced by fat, the aponeurotic and areolar frame-work of the organ acquiring a marked predominance over the fleshy substance, and what has been termed the fibrous transformation being produced. In the present state of science we are unable to point out the physical and physiological conditions by which these two results are determined. Fatty infiltration may invade a tense or a relaxed muscle, and in the same muscle two neighbouring fasciculi may present the two different changes. M. Guerin regards the fatty transformation as consecutive to paralysis, and the fibrous transformation as the ultimate stage of muscular retraction. M. Robert, however, quite" agrees in the conclusions of M. Bouvier, who has dissected various muscles affected with old contractions, without ever observing transformation of fleshy into fibrous or tendinous structure. The tendons in such cases participate in the atrophy of the fleshy parts. M. Broca, prosector to the faculty, has also dissected 5 specimens of congenital club-foot, and about 15 other specimens, the congenital origin of which was doubtful; and in none of these has he met with this fibrous transformation.

2. Classification.—M. Robert distributes the various forms of congenital deformity of the joints into four groups, dependent upon anchylosis, diastasis, the absence of bony parts, and deviation or luxation.

(a.) Deformities of the Joints dependent upon Congenital Anchylosis.—This may be complete, so as to induce absolute immovability of a joint, or incomplete, so as only to considerably reduce the extent of its movements. M. Robert refers to a case of congenital union of the calcaneum and cuboid bones observed on both sides; and to another in which the calcaneum and the scaphoid formed on both sides but a single cartilaginous mass, having a distinct point of ossification for each bone. He also quotes at full length a remarkable case from the Bull, de la Soe. Anat., 1836. A man died, aged 27, whose left arm was seven inches shorter and much smaller than the right, and was said to have been always so. Besides other changes in the skeleton, a flat or rather slightly convex surface was found in place of the glenoid cavity of the scapula. The humerus had no head, but possessed a slightly convex articular surface, stretching obliquely downwards and inwards, at the place of its usual neck. This bone was larger below than above, and was so absolutely united to the radius, that no

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