found tubercle bacilli in the stools of persons affected with tuberculosis of the intestines.

In purulent discharges from the ear of the phthisical, tubercle bacilli have been frequently found, e.g., by Eschle,' Voltolini 2 (in two of his cases caries of the petrous bone was also present), Ritzefeld, and Nathan (in three of his cases there was also caries of the mastoid process, or of the smaller bones of the ear). Lastly, Habermann 5 was able to recognise tubercle bacilli in a number of corpses, who in life had been affected with tuberculous changes in the middle ear.

To these must be added various scrofulous discharges; Holtz for instance has found tubercle bacilli in the glandular swellings of scrofulous affections, in certain kinds of eczema and subcutaneous abscesses; Volckman' has even found bacilli in the scrapings of the epidermis of scrofula.

There have been several exact researches as to the disinfection of tubercle, the leading one being that of Dr. Fischer, who discovered the remarkable power of aniline water as a disinfectant for tuberculous sputum. If sputum be treated with ten times its bulk of aniline water and allowed to remain in contact 24 hours, it is fully disinfected, but he at the same time points out that considering the relative price of aniline water and that of carbolic acid, the latter is preferable; he found that 5 per cent. carbolic acid added in equal bulk to the sputum and acting for 25 hours fully disinfected.

Corrosive sublimate did not give so favourable a result: 1 to 500 solution added to sputum in the proportion of one part of sputum and one of the sublimate solution failed to disinfect. In all the above the result of the disinfection was ascertained by subcutaneous injection of the disinfected and undisinfected sputum into animals.

A heat of 100° when dry sometimes failed to disinfect, although it acted during 60 minutes. Boiling for 10 minutes, or a steam heat acting for 15 minutes disinfected perfectly.

Yersin has made some experiments by the "thread" method

described at page 315. This method is of course inferior to that of direct inoculation, but it has its value. He gives the following as the result of his experiments with the bacillus of tubercle:

He also studied the action of heat, and declares that at a temperature of above 70° sterilization is effected.

(359) The Prevention of Tuberculosis.

The Medical Officer of Health at present is neither aided by public opinion nor by statute in any attempt he may make to directly stop the propagation of tuberculosis. The only way open to him is to direct his attention to dampness of habitation, to overcrowding, to tuberculous meat and to diseased milch cows; in all these points he has a certain amount of power, but to isolate the affected person, to disinfect articles infected with tubercle bacilli, he has no power, unless he can get his authority to consider tuberculosis as an infectious disease" under the 120-122 sections of the Public Health Act. This will no doubt come in time, but the knowledge that the medical and scientific world possess is distinctly in advance of the knowledge of the people at present. The people will have to be educated on this matter, and once the danger of "catching" consumption is fully recognized, there will be no difficulty in the first place of obtaining power to isolate those cases where there is likely to be danger to the healthy, and in the second place to have each case notified to the sanitary authority. From the large number of victims to tuberculosis in this country, it is a far more important malady to have notified than such purely infantile complaints as measles.

Phthisis and miliary tuberculosis should be treated in a public health sense exactly as an infectious fever, the sufferer should be isolated, the liquid and solid excreta disinfected, preferably with

10 per cent. carbolic acid and the sputum of the phthisical received on rags or paper and burned. The propagation of tuberculosis by milk is to be met by a more rigid inspection of milch cows than has heretofore been made, and when proper abbatoirs are established throughout the country a strict meat inspection will then be possible, but until that is done a very large amount of the meat consumed must be derived from tuberculous animals.

CHAPTER XXXI.

MALARIA-MALARIOUS DISEASES.

(360) The Effects of Malaria.

UNDER the somewhat indefinite term of malarious diseases is meant those maladies which experience has shown to be intimately connected with a particular condition of soil.

Malarious soils are all more or less marshy, or are tracts in the vicinity of marshes; places which are well drained or dry, and those which are covered with water are not malarious. The diseases are thus intimately connected with some particular kind of vegetable decomposition.

The effects of malaria in their lightest form express themselves as neuralgias of an intermittent type, or as epidemic jaundice; the author, for instance, has noticed that in a malarious tract from time to time occur a number of almost simultaneous cases of more or less pronounced jaundice without fever or other symptom; but the most typical malady of all connected with malaria is that of ague or intermittent fever. In the hotter parts of the world there is also yellow fever; this has several analogies to the intermittents.

(361) Bacteriology of Malarious Diseases.

Probably there are several kinds of micro-organisms which produce as many varieties of intermittent fever. Klebs and Crudeli1 have, however, isolated from cases of intermittent fever a bacillus from 2 to 7 μ long, which is capable of growth into twisted threads. Spore formation takes place at the centre or at either end. Marchiafava has also discovered in the blood of persons

1 Archiv. f. Experimental Pathol. 1879.

2 Ibid.

suffering from intermittent fever similar bacilli with end spores. These kinds, if indeed they are not identical, have been found in the soil of the Roman Campagna. Inoculated into rabbits they produce an intermittent fever, and in the spleen and marrow the threads and spores are found in abundance. There have also been found in the blood in cases of malaria amoeboid bodies and motile filaments.

The modern theory, therefore, is that these bacilli or analogous micro-organisms are produced in vast numbers in malarious soils, that the spores are raised by evaporation or by the agency of wind, that they float in the atmosphere, fall with the night dews, and are breathed into the lungs or swallowed with the food or saliva and produce the maladies enumerated.

(362) Geographical Distribution of Malarious Tracts.

In this country the fens of Norfolk and Lincolnshire used to be noted haunts of malaria, but the drainage of both these counties has reduced the number of cases greatly, and fatal ague is quite an insignificant cause of death in the Registrar-General's returns. It is in the deltas, the marshy banks, and the embouchures of rivers that agues are to be looked for. In Europe the Italian maremma,1 the plains of Walcheren and of Rosendaal, the lines of detached pools along the Guadiano in Spain, impress their malarious character on the memory as a cause of great mortality of armies in the historical campaigns. In India the stations of Calcutta, Chinsurah, and Berhampore are highly malarious. In America malaria hangs about the Orinoco, the Amazon, and other great rivers; in short, there is scarcely a country in the temperate and torrid zones which have not portions of moist and swampy land dedicated to malaria.

(363) Malaria from Local Causes.

Malaria may spring from essentially local and removable causes. The Medical Officer of Health may find from careful inquiry that in a particular group of houses or in a particular house from time to

1 A good account of the Italian maremma and the history of intermittent fever in Italy is given in Lettres écrites d'Italie en 1812 et 1813, par F. Sullin de Chateauvreux. Paris, 1816.