II. THE SUB-ACUTE OR CHRONIC LOCAL INFECTIVE 

 DISEASES. 



CHAPTER I. 

 TUBERCULOSIS* 



BACILLUS TUBERCULOSIS (KOCH).* 



General Characteristics. A non-motile, non-flagellate, non-spor- 

 ogenous, non-liquefying, non-chromogenic, distinctly aerobic, acid- 

 resisting, purely parasitic, highly pathogenic organism belonging to 

 the higher bacteria. It commonly occurs in the form of slender, 

 slightly curved rods with rounded ends, but not infrequently shows 

 distinct branches. 



Tuberculosis is one of the most dreadful and, unfor- 

 tunately, one of the most common diseases. It is no 

 respecter of persons, but affects alike the young and old, 

 the rich and poor, the male and female, the enlightened and 

 savage, the human being and the lower animals. It is the 

 most common cause of death among human beings, and is 

 common among animals, occurring with great frequency 

 among cattle, less frequently among goats and hogs, and 

 sometimes, though rarely, among sheep, horses, dogs, and 

 cats. 



Wild animals under natural conditions seem to escape 

 the disease; but when caged and kept in zoologic gardens, 

 even the most resistant of them lions, tigers, etc. are 

 said at times to succumb to it, while it is the most common 

 cause of death among captive monkeys. 



The disease is not limited to mammals, but occurs in a 

 somewhat modified form in birds, and, it is said, even at 

 times affects reptiles, batrachians, and fishes. 



The disease has been recognized for centuries ; and though, 

 before the advent of the microscope, it was not always clearly 

 differentiated from cancer, it has not only left unmistakable 

 signs of its existence in the early literature of medicine, but 

 has also imprinted itself upon the statute-books of some 

 countries, as the kingdom of Naples, where its ravages were 

 great and the means taken for its prevention radical. 



Specific Organism. Although the acute men of the early 

 * "Berliner kHn. Wochenschrift," 1882, 15. 

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