Tuberculosis. 115 



ly, it depends on the intensifying and fixing of personal and fam- 

 ily characters. The susceptibility to the germ being equally 

 strong in both parents becomes intensified in their common ofi"- 

 spring just as the beef or dairy characteristics are improved. 

 Indeed, the qualities which make an animal valuable; for the 

 butcher or milkman are exactly such as favor tuberculosis. The 

 germ of this disease lives by preference in the lymphatic system, 

 either in the lymphatic glands or in the loose connective tissue 

 forming the lymphatic networks leading to these glands. Now 

 the breeds which are preeminent for early maturity, and rapid 

 fattening, or for a high yield of milk are remarkable for their 

 excess of connective tissue, as shown by the delicate mellow skin, 

 and in the case of the Channel Island cattle by the unusually 

 large lymphatic glands. This helps to explain why certain fam- 

 ilies of beef-making cattle have been virtually ruined by tubercu- 

 losis. Yet it would be equally wrong to abandon the improve- 

 ment of our beef and of our milking breeds. The improvement 

 already attained is essential to successful competition in the 

 market, and prospective improvement will be no less essential in 

 the future. The true and only real remedy is the extinction and 

 exclusion of the bacillus of tubercle. 



£■. Ill Health. 



All acute and chronic diseases leave the system weak, and with 

 less power of resistance to other diseases. Above all we must 

 fear long standing diseases which produce emaciation and weak- 

 ness, fevers which interfere permanently with the blood-forming 

 processes, diseases of the digestive organs, which hinder the 

 requisite preparation and absorption of nutritive elements, and 

 diseases of the lungs which form a raw or weakened surface on 

 which the bacillus can grow without hindrance. Again the germ 

 lives best in a slightly alkaline or neutral medium, and is weak- 

 ened in the acid contents of the stomach during vigorous diges- 

 tion. But in indigestion the contents may be too much lacking 

 in acidity to prove hurtful to the germ, and the imperfectly di- 

 gested morsels, enclosing the bacillus, may be passed on un- 

 changed into the alkaline intestine, a field especially favorable to 

 the development of tuberculosis. Again in the intervals between 

 meals when the acid secretion is arrested, the bacillus in drinking 



