58-2 Tra una c t ivii s . — 311 sec U a nco us . 



result. Guinea-pigs and rabbits fed constantlv on food cou- 

 taining tubercle germs in time developed the disease, and 

 the examination of their bodies sho^Yed that the germ evi- 

 dently entered tlie system through the walls of the bowels 

 and thence invaded the rest of the body. 



While tuberculosis most frequently affects the lungs in 

 young adults, it is found that in young children it is especially 

 the bowels and the adjacent parts that are affected. The 

 examination of the bodies of children thus dying points out 

 conclusively that the germs have entered the body through 

 the walls of the bowels and spread thence. Such disease in 

 children is especially frequent between the first and sixth 

 years of life, and forms one of the most common causes of 

 death during this period. The difference of the localities in 

 the body which tuberculosis especially affects in adults and in 

 children is explained by the fact that during early childhood 

 the digestive system is especially taxed. The rapid growth of 

 the body causes a demand for a large amount of digested 

 matter to supply material for building up the tissues, and this 

 demand throws so heavy a strain on the digestive organs that 

 they are especially liable to be thrown out of order and 

 rendered less capable of resisting disease. 



It being probable that the germ of tuberculosis is able to 

 make its inroads on the human frame by way of the alimen- 

 tary tract, introduced in the first place with the food, it will be 

 readily perceived how important it became to find out in what 

 form of food the germ is liable to be present. Many faCts 

 pointed to the probability of animal food being an agent of 

 infection — in fact, that a vast unknown accidental infection 

 by this means had been going on for ages. 



In cattle a disease exists known as bovine tuberculosis, 

 unfortunately at the present time on the increase, and affect- 

 ing especially the best breeds of dairy-cattle. This disease 

 has during the last few years been shown to be due to the 

 very same cause as the similar disease which plays such havoc 

 with the lives of men, and it exists to such an extent and 

 under such circumstances as to leave little doubt that much of 

 the tuberculosis in man is due to infection through the use of 

 meat or milk from tuberculous cattle. In 1881 the authorities 

 of the Grand Duchy of Baden issued a report which applied to 

 fifty- two towns, and which showed that where tuberculosis 

 was prevalent among cattle it was eqirally prevalent among 

 the human population, and was more prevalent in those parts 

 of a town where the butchers paid least attention to the 

 quality of the meat sold. Sir Lyon Playfair has recently in a 

 (lebate in the British House of Conuuons pointed out that it is 

 a significant fact that where tuberculosis in cattle increases 

 there also consumption in its different forms increases, but 



