in producing diseases of the circulatory organs, and the greater suffering from it of young soldiers, seems certain. The statistics in the Knapsack Committee's Report confirm this.

The cause of this preponderance in the army of diseases of the circulatory organs is a matter of great importance. Whatever they may be, it is probable that they produce both the cardiac and the arterial disease.

The two most common causes of heart disease in the civil population are rheumatic fever in young, and renal disease in older persons. The latter cause is certainly not acting in the army, and the former appears quite insufficient to account for the facts. A great number of the men who suffer from heart and vessel disease have never had acute rheumatism; and if we refer the affection to slight attacks of muscular rheumatism, which almost every man has, we are certainly going beyond what medical knowledge at present warrants. The effect of lung disease in producing cardiac affections is also not seen in the army to any extent.

The influence of syphilis in producing structural changes in the aortic coats was noticed by Morgagni. In 114 post-mortem examinations of soldiers dying at Netley, Dr. Davidson' found 22 cases of atheroma of the aorta. Of those 17 had a syphilitic history, 1 was doubtful, and 4 had had no syphilis, but had heart and lung diseases. Of the whole 114 cases, 78 had no syphilitic history and had 4 cases of atheroma, or 5.1 per cent.; 28 had a marked syphilitic history and 17 had atheroma, or no less than 60.7 per cent. This seems very strong evidence as to atheroma. With respect, however, to actual aneurism, no corresponding analysis of cases has been made, and therefore at present the effect of syphilis must be considered uncertain; but it is quite clear, even admitting its influence, there is no reason to think that syphilis prevails more among soldiers than among the civil male population of the same class. It is, therefore, unlikely that an excess of syphilis, if it really occurs among soldiers, and if it actually predisposes to aneurism, as seems probable, could produce 11 times as many aneurisms as in civil persons. Myers has also given evidence that both in the army and navy aneurism is sometimes not preceded by degeneration of the arterial coats, and in these cases mere improper exertion seemed to produce it.

The effect of excessive smoking again has been assigned as a cause of the soldier's cardiac disease; but no one who knows the habits of many continental nations, and of some classes among our own, could for a moment believe this to be the cause.

Again, the effects of alcohol in constantly maintaining an excessive action of the heart, are so marked as to make it highly probable that this is a fact of great importance; but soldiers do not drink so much, as compared with civilians, as to lead us to think the cause can explain the prevalence.

2

There is, however, one cause which is continually acting in the case of soldiers, and that is the exertion (often rapid and long continued) which some of the duties involve. The artillery have very heavy work; often it is very violent and sudden, more so perhaps than in any other corps; the cavalry also have sudden work at times; and the infantry soldier, though his usual labor is not excessive, is yet sometimes called upon for considerable exertion, and that not slowly, or with rests, but with great rapidity. And this exertion

1

Army Medical Department Report, vol. v., p. 481.

* For a full and able discussion on all those points, and for additional evidence, reference must be made to Mr. Myers' excellent work. On the effect of exertion during war in causing cardiac hypertrophy, reference may be made to Dr. Fräntzel's paper in Virchow's Archiv, Band lvii., p. 215.

is in all arms undertaken with a bad arrangement of dress and of equipments. The cavalry and artillery men are very tightly clothed, and though the horse carries some of the burden, it is undoubted that the men are overweighted. In the infantry, till lately, they wore very tight-fitting tunics, with collars made close round the neck, and trousers (which were often kept up by a tight belt); there was a broad strap weighted below with a heavy pouch and ammunition, crossing and binding down the chest; and there was the knapsack constricting the upper part of the chest, and hindering the air from passing into the proper lobes.

The

The production of heart disease ought not to be attributed solely to the knapsack, as is sometimes done; the knapsack is only one agency; the crossbelt was probably worse, and the tight clothes add their influence. But even with the knapsack alone the effect on the pulse is considerable, and one or two of Dr. Parkes' experiments may be given in illustration. Thus, four strong soldiersc arried the old regulation knapsack, service kit, great-coat, and canteen, but no pouch and no waist-belt (except in one man). pulse (standing) before marching was on an average 88; after 35 minutes it had risen on an average to 105; after doubling 500 yards, to 139, and in one of the men was 164, irregular and unequal. After the double they were all unfit for further exertion. In a fifth man, who was not strong, the 35 minutes' marching raised the pulse from 120 to 194; after doubling 250 yards, he stopped; the pulse then could absolutely not be felt. In another series, the average pulse of four men, with the knapsack only, was 98 (standing), after one hour's march, 112; after their doubling 500 yards, 141. If the pouch with ammunition is added, the effect is still greater. Dr. Parkes also took the pulse and respirations after long marches, and found the effect still more marked. Walking, of course, will quicken the pulse and respiration in any man, but not to such an extent, and the sense of fatigue in unincumbered men is much less.

In the lecture formerly alluded to,' Dr. Maclean put this matter most forcibly before the authorities, and he is undoubtedly quite justified in the expression that one cause of the cardiac (and perhaps of the aortic and pulmonary) disease in the army is to be found in exertion carried on under unfavorable conditions.

2

Happily, much has been lately done by the authorities to remove this cause; but still, especially in the artillery and mounted service, changes appear to be necessary, and in all arms it is desirable that officers should allow their men to do their work under the easiest conditions, as regards clothes, weights, and attitudes, consistent with military discipline and order.

3. THE NERVOUS DISEASES.

These form a very heterogeneous class; apoplexy, meningitis, paralysis, mania, etc., are the chief headings. The proportion to 1,000 of strength is about .6, and 6.6 deaths of every 100 are owing to nervous diseases.

1 Royal United Service Institution Journal, 1863, vol. viii.

2 The cardiac diseases are of the most varied kind. Dr. Parkes wrote-"I have seen at Netley, in Dr. Maclean's wards, in one hour in the summer, when the hospital is full, almost all the combinations of heart affections. It has appeared to me that if anything gives the tendency to heart affections, then the dress and accoutrements come in as accessory causes, and prevent all chance of cure. In some cases there is no valvular disease, and not much hypertrophy of the heart, but a singular excitability, so that the heart beats frightfully quick on the least exertion."

As among the male civil population (ages 25 to 35) the deaths are also 6.6 per cent. of total deaths, soldiers do not appear to suffer more.

4. PNEUMONIA AND ACUTE BRONCHITIS.'

TABLE to show the admissions and deaths per annum, per 1,000 of strength, years 1859-71 (thirteen years).

The acute inflammatory diseases of the lungs give, therefore, a mean annual mortality of .856 per 1,000 of strength. The mean total deaths from diseases of the respiratory system, for the nine years (1872-80) was 1.34 per 1,000, causing 17 per cent. of total deaths.

In the French army pneumonia gives a lower, and acute bronchitis a higher, mortality than in our own, but this is perhaps a mere difference of nomenclature.

The opinion that the military suffer more than the civil population from pneumonia is an old one. It is also generally believed that they suffer less in the field than in garrison. Trustworthy statistics seem wanting as to the amount among the civil population. In the European population, generally, Ziemssen gives the deaths from pneumonia as 1.5; and Oesterlen,' 1.25 per 1,000; but this includes all ages, and both sexes. Among men alone it is certainly greater than among women. In London, in 1865, the mortality from pneumonia, between the ages 20 and 40 (both sexes), was 1 per 1,000 population.*

If this be correct, the mortality among soldiers is below the civil mortality, or soldiers are less subject than civilians; for, as men are more subject to pneumonia than women, the mortality among the civilian males would be greater than 1 per 1,000, but the military mortality is only .641. The mortality among the army pneumonic cases (deaths to treated) amounts (average of thirteen years) to 12.18 per cent.," and as this is very nearly the civil proportion, every 1,000 of population in London gave nine cases of pneumonia, while 1,000 soldiers gave only five. It may be said, however, that London is not a fair test; but as a place of residence for soldiers it does not appear to predispose to pneumonia, as will be seen from the following table:

Separate data are not published in the Army Medical Reports, for the later years. 'Monats-Bl. für Med. Stat., 1857, and Schmidt's Jahrb., 1862, No. 3, p. 337.

3 Med. Statist., 2d edit., p. 567.

Vacher, Sur la Mort. en 1865, Paris, 1866, p. 137.

In thirteen years there were 4,826 cases treated, and 588 deaths, or 12.18 deaths per cent. In Canada the deaths to admissions were only 7.13 deaths per cent. (average of twelve years ending 1870).

The mortality to cases treated in the five years (1867-71) was, in the Guards, 10.68, and in the infantry, 11.7 per cent.

Although it does not seem that pneumonia (and acute bronchitis?) are more common or more fatal among soldiers serving at home than among civilians, the above figures show what a fatal disease pneumonia is, and how worthy of renewed study its causes are.

5. THE CLASS OF CONTINUED FEVERS.

The returns do not carefully distinguish the several forms, but practically the majority of the fatal cases of "continued fever" are from enteric (typhoid) fever.

There has been a great decline in this class of late. In the ten years (1837-46) the average admissions were 62, and the deaths 1.72 per 1,000 of strength. In the eight years ending 1867, the admissions averaged 22, and the deaths .5 per 1,000 of strength. In 1871 there were only 80 cases of enteric fever and 22 deaths in the whole army of 87,000 men. In the four years ending 1875 the mean total deaths from continued fever were 0.37 per 1,000, and they amounted to 4.4 per cent. of the total deaths. In the five years ending 1880 the total deaths were 0.30 per 1,000, and the numbers to total deaths 4.1; in 1880 the numbers were respectively, 0.26 and 3.8.

This mortality is decidedly below that of the male civil population of the same age, which amounts to 9.6 per cent. of total deaths, and very nearly 1 per 1,000 of population.

During late years no points have been more attended to in the army than pure water supply and good sewerage, and we see the results in this very large diminution of deaths from the rate of the former period, and in the fact that in this particular class of disease the soldier is far better off than the civil population. So also the cholera of 1866 passed very lightly over the army at home (only 13 deaths out of 70,000 men), although in former epidemics the army suffered considerably.

The decline of enteric fevers confirms most strongly the doctrine of its intimate dependence on bad sewage arrangements.

The greatest amount of typhoid fevers in the army is in the garrisons in the seaports, the least in the camps.

The other classes of disease causing mortality need no comment. Chronic bronchitis is no doubt to be chiefly referred to phthisis (using that term as a generic word to include various disorganizing lung diseases), and delirium tremens is a return which will, no doubt, gradually disappear in fact, as it has already done in figures from the published Reports.

The smaller items of mortality, making up about 22 out of every 100 deaths, are various; erysipelas, pyæmia, syphilis, hepatitis (in men from foreign service), enteritis, rheumatism (from heart complication probably, but returned as rheumatism), diabetes, ebriositas, scarlet fever, and diphtheria, are a few of the many causes which carry off a small number every year. The cancerous and kidney diseases are very few, as we might expect from the age of the men.

To sum up the case as regards the present mortality on home service, it may be stated that for the last twenty-one years (up to 1880) there has been some lessening, but no great fall in the number of deaths. There is still much to be done in respect of preventing disorganizing lung disease, disease of the circulatory organs, and even fever, for we ought not to be satisfied until the term enteric fever is altogether obliterated. A renewed study of the causes of pneumonia is also necessary, in order to see if some

way or other the attacks of that fatal disease cannot be lessened. There is no reason to think that we have yet touched the lowest possible limit of preventable disease; but, on the contrary, we can see clearly that the soldier, comparatively healthy as he is, may be made more healthy still. Some evidence in support of such a view may be found in the fact, that both at Gibraltar and in some of the West Indian stations the mortality has been lower in some years than it has ever been at home. But there is no reason why the home mortality should not be reduced to the standard of those foreign stations.

A question now arises-Why, after thirty years of age, should the soldier die more rapidly than the civilian, though for the first ten years of his service he has a smaller mortality? The causes may be foreign service, bad social habits (i.e., excess of drinking and syphilis, or other effects of enforced celibacy), night duty, exposure on guard, and prolonged influence of impure barrack air. But to which of these the result is owing could only be determined by accurate statistical inquiries of the causes of mortality at the older ages. We do not know these, and if the short service system continues we are hardly likely to know them, so it is of no use to discuss a topic on which sufficient facts are not available.

B. LOSS OF STRENGTH OF THE ARMY BY INVALIDING.

The amount of invaliding is influenced by other causes than mere inefficiency of the men; sometimes a reduction is made in the army, and the opportunity is taken to remove weakly men who would otherwise have continued to serve. This was the case in 1861. As invaliding greatly affects the mortality of the army, a source of fallacy is introduced which it is not easy to avoid.

During the seven years (1860-66), there were invalided every year nearly 37 men out of every 1,000, thus making a total loss by death and invaliding from disease of nearly 46 men per 1,000, or about one-twentysecond part of the whole force. In 1867 the invaliding was lower, viz., 22.18 per 1,000. For the ten years (1870-1879), the invaliding in the United Kingdom was at the rate of 27.18 per 1,000, and the deaths were 8.18, -making together 35.36, or one-twenty-eighth part of the force. For the whole army the numbers were, 22.15 and 12.67-together 34.82, or slightly less. In 1880 the total loss for the United Kingdom was only one-thirtyfourth, and for the whole army one-twenty-eighth. The causes of the invaliding were formerly very carefully ascertained by Dr. Balfour, and inserted in his Reports, but the information is now omitted from the " Army Medical Department Reports." Speaking in round numbers, for the period when detailed returns were furnished, phthisis and scrofula account for about one-fourth of the invalids, and if chronic bronchitis was included, for nearly seven-twentieths, the two items of hypertrophia cordis and morbus valv. cord. accounted for one-tenth, and chronic rheumatism for one-fourteenth. The three nervous diseases of amentia, mania, and epilepsy always caused a large number of invalids, amounting nearly to onetenth, or almost the same as the two classes of heart diseases. All the other items were smaller. In men invalided under one year's service nearly one quarter were so from epilepsy; the remaining chief causes were phthisis and diseases of the circulatory organs. It is probable that the loss from invaliding will continue to diminish as a consequence of the short service system.