ous, according to the quantity of phosphorus | CH. ROUCHER, Annales d'Hygiène, 1874, t. ii. present. The distillate, which should be p. 406.) received in a small bottle, will be acid, and will, on being shaken, exhibit a luminosity. The distillate may be treated with a little pure nitric acid, evaporated to a small bulk, and tested qualitatively for phosphoric acid by the usual tests. It may also be estimated by precipitation with ammonia and sulphate of magnesia, the resulting precipitate washed, dried, ignited, and weighed, and the amount of phosphorus calculated out from the pyrophosphate of magnesia. Free phosphorus often cannot be found even when known to have been taken; the reason of this is that it has undergone oxidation, and appears under the form of phosphoric acid. In cases where no free phosphorus is found, it has been recommended by some chemists to estimate the phosphoric acid found in the stomach, or even in the tissues. Such a process must inevitably lead to disastrous errors. Phosphates exist in all parts of the body, and even crystals of the ammonia-magnesian phosphate may be found in people who have not taken any free phosphorus, especially when the organs are in a state of decomposition; nor is the phosphoric acid naturally present in the body, fixed and invariable. Jules Lefort found 179 per cent. of phosphoric acid in the muscles of a man who died from disease at La Pitie, and in the muscles of another corpse, that of a man who died from accident, 333 per cent. was found. The liver, the stomach, the lungs, &c., of different subjects, yielded variable quantities of phosphoric acid. must also be remembered that the different varieties of food found in the stomach nearly all contain phosphoric acid, e.g.— It Phosphates. Per cent. 0.049 0.395 0.398 0-361 0:458 0:387 0.345 0:465 0.514 0.532 Brain of ox (white and grey substance) 0-503 Tripe 0.760 -(Recherche Toxicologique du Phosphore, Annales d'Hygiène, 1874, ii. p. 405.) Antidote.-The evidence appears pretty complete that oil of turpentine is a true antidote to phosphorus. The dose should be about a teaspoonful every four hours.-(See Arsenic, Phosphore, et Antimonie, par M. le Docteur Phthisis, Consumption, Tuberculosis, &c.-Although there are differences between phthisis, consumption, and tuberculosis, they are only such as have been pointed out of late years by a more accurate and extended pathology; hence it will be convenient for the study of consumption statistics to define, for the purpose of this article, the term "phthisis" as a disease of the lungs attended by wasting, and returned in the Bills of Mortality as tissic, in the Registrar-General's as phthisis, or tubercular disease, and signified by other writers as consumption, dry-rot, &c.; and it must be premised that a percentage of many other diseases-such as chronic bronchitis, emphysema, fibroid changes of the lung-have been for many years returned as phthisis. It is, however, probable that the figures representing the mortality are fairly accurate, as the errors are to a certain extent compensating; and indeed tubercles are often found even in the diseases above mentioned. The pathology of phthisis may be shortly stated thus, that there is a production in the lungs and other organs of a morbid product called tubercle, either in the shape of little, grey, almost structureless masses, or a yellow cheesy-like substance, which is either scattered more or less uniformly through the tissue, or is collected into larger or smaller masses. The tissue around each little mass generally inflames and ulcerates, the ulceration and suppuration being an effort of nature to get rid of the foreign substance. Thus, by successive ulceration a large portion of the lung may be destroyed, or by inflammation of such a tissue as the peritoneum, or the meninges of the brain, a fatal result be rapidly attained. Recent researches would appear to show that tubercle begins in the lymphatics, the first changes being in the epithelial cells (endothelium) lining those vessels. It will be convenient to first prove the importance of the study of consumption to hygienists by referring to the mortality from this disease. 66 Table I., on p. 441, shows the number of deaths from consumption within the London Bills of Mortality from 1629, with several breaks, down to 1832, and is taken from the Insurance Cyclopædia," art. Consumption. Consumption occupies the first place in the causes of death. For instance, in the Registrar General's returns for 1871, phthisis comes first, with the proportional number of 2364 to 1,000,000 deaths from all causes. Then bronchitis, with the proportional number of 2112 to 1,000,000 deaths from all causes. TABLE I.-Showing the Number of DEATHS from CONSUMPTION within the LONDON BILL OF MORTALITY from 1629 (with several breaks) down to 1832. extract and table occur, both of which are in- | ally in crowded ships, barracks, and rooms. structive: Contagion of Consumption. -It has long been firmly believed in Italy that consumption is contagious, but that, generally speaking, it is not so, is sufficiently proved, as Dr. Guy remarks, by the small fluctuations of the annual mortality from this cause. The lowest number of deaths from consumption, for a million of inhabitants of London, for any one of the fifteen years from 1840 to 1854 inclusive, was 2645, and the fluctuation is very slight. The figures in three consecutive years were as follows: 1849, 2777; 1850, 2645; 1851, 2970. "If then," Dr. Guy says, "any one were to assert that this disease is contagious, which is tantamount to saying that it may be epidemic, the figures I have quoted would in themselves furnish an answer in the negative. They are suggestive of a domestic disease, influenced as is bronchitis by the seasons and the weather." The same small fluctuation is shown, if the twenty years from 1850 to 1869 are taken. In the whole twenty the mean annual rate of the deaths from consumption was 3449 1. In the first ten of these years, 1850-59, it was 35514; in the second ten, 3346 8 or dividing the whole period into four equal parts of five years each, for the first quarter we have 3665 as the mean annual rate, for the second 3448, for the third 3367, for the fourth 3326-the lowest number being 3326, the highest 3665. There are, however, instances in which phthisis would appear to be contagious, especi Dr. Guy indeed mentions a certain printing. house where the workmen died from consump tion as fast as if it was contagious. And Dr. Farr in 1815 said, "The prevalence of phthisis in the armies of Europe is probably due in part to the inhalation of expectorated tubercular matter, dried, broken up into dust, and floating in the air of close barracks." But it must be remembered that in all crowded localities there is direct vitiation of air, and it is difficult to say whether the foul air or actual contagious particles have most to do with the propagation of the malady. In short, consumption under ordinary conditions is certainly not contagious; but under special insanitary influences, certain forms of consumption may be contagious, although it is still a matter not proven. Causes.-These may be divided into two great classes: the one comprising all those predispositions which from a variety of causes exist in the constitution of the individual himself, such as hereditary influence, sex and age, &c.; the other class comprising influences external to the body, such as impure air, occupation, clothing, peculiarities of the soil, climate, &c. Although these causes will be dealt with seriatim, those of the second might be reduced to (1) exposure to cold and wet; (2) impure air, whether from deficient cubic space or the following of an unhealthy occupation; and (3) dampness of soil. Hereditary Influences. -We have not the slightest doubt that this influence has been much exaggerated; it must be remembered that it is one of those influences so mixed up with other surroundings that it is often im. possible to estimate it apart. For example, the father and mother of a family die of consumption, and the children show signs of it; but it will generally be found that these children have been subjected to the same soil, to the same air, and to the same house which developed the phthisis of their parents, yet the cause would probably be put down to hereditary influence! It is this identity of external conditions and occupations amongst many families that swells the figures of so-called hereditary transmission. There are, without doubt, instances pure and simple of this transmission, especially in those cases of general tuberculosis, that every physician must meet with, in which a young person, of a marked strumous appearance, born of diseased parents, yet with every favourable external condition, dies of consumption. There is an accidental consumption, and there is a constitutional consumption. There is a consumption that arises from a common cold, in which the inflammatory | consumption than men, old people less liable action, first in the bronchial tubes, insidiously than young and middle-aged. Women are extends itself to the air-cells of the lungs, and more exposed to the bad hygienic condition of thus being accidental, can hardly be trans- an insanitary dwelling; and old men, from the mitted, at all events to children begotten be- very fact of their being old, are, so to speak, fore the disease was contracted; and there is selected lives. Sir James Clark showed that a consumption the seeds of which are constitu- in seven cities in Europe and America there tional or latent, the germs of which are born is a pretty uniform decline in the ratio of with the individual, and ready to light up on deaths from phthisis from twenty years to the least exciting cause. This latter may be, extreme age. and frequently is, transmitted. Medical men to insurance companies should not alone study the bare figures, which give an exaggerated idea of hereditary influence, but inquire as to the conditions under which the consumptive progenitor existed. Dr. Brinton found that among hospital consumptive patients, about 90 per cent. had lost some of their nearer relatives by what appeared to be the same disorder; "and that instead of 1 out of 10 (the average mortality), about 3 had thus died." In relation to this he says further: "There is an impression (which is favoured by some well-known facts in the physiology of generation) that the tendency to phthisis is more likely to be transmitted by a mother than by a father thus diseased. Other things being equal, it may be so; but such preponderance is often outweighed by a strong and predominant likeness of the offspring to either of their parents. For such an external likeness may well be supposed associated with an equal similarity of constitution, especially where it involves the framework of the thoracic cavity, in which the disease chiefly shows itself. Hence, though the father of one subject may have died of decline, still if he himself takes strongly after his mother, this resemblance to the healthier branch of his ancestry goes far to nullify the injurious suspicions which his father's death might otherwise have excited." (On the Medical Selection of Lives for Assurance, by Dr. Brinton.) According to the medical officers of the Brompton Hospital, as to the proportion of cases on the books in which hereditary taint could be traced, out of 1010 cases, comprising 669 males and 341 females, 122 males and 124 females (forming 18 and 36 per cent. respectively of the whole, or 24.5 per cent. of males and females combined) were born of phthisical parents; or, in other words, 1 in every 4 of the 1010 patients was descended from consumptive parents. As hinted at before, all these figures, as they do not distinguish between accidental and constitutional consumption, are to be looked upon with suspicion. Sex and Age.-The influence of sex and age is indisputable. Women are more liable to In Edinburgh the ratio was found to decline from 285 at twenty years, to '052 above sixty years; at Nottingham, from 416 to 017 in the same period of time; at Chester, from 245 to 054; at Carlisle, from 290 to '097; and in Paris, according to Louis, from 325 to 042: while the general average decline was from 285, or 28 5 per cent., at twenty to thirty, to 078, or 780 per cent., above sixty. Dr. Guy prepared the following table, showing the deaths from consumption in 1000 males and 1000 females of the population of England and Wales, and of London respectively, living in 1851, at decennial ages :TABLE IV. Occupation. In the consideration of occupation as influencing the disease, the differences we meet with are striking and remarkable, especially as regards outdoor and indoor employments, and residence in town or country. With respect to the latter, the death-rate from comsumption and other diseases of the respiratory organs was stated by Dr. Farr in 1843 to be 782 in towns, against 5-22 in country districts, to each 100,000 living; but the actual rate is much higher than this, for the country returns are exaggerated by many artisans and others, who, born in the country, contract their chest affection in the town and return home to die. The influence of indoor against outdoor occupation is shown in the following table : TABLE VII.-DEATHS from TUBERCULAR DISEASE at the VICTORIA PARK HOSPITAL, showing the influence of Occupation. |