456 TUBERCULOSIS. 



should say this condition was less frequent after catarrhal than 

 after croupous nephritis. In the first instance, the waxy 

 degeneration invades a pale or dark-brownish-red kidney, or it 

 may be confined to the pyramidal substance only j while in the 

 last instance the lardaceous appearance is uniformly distributed 

 throughout the organ. 



Out of two hundred cases of tuberculosis of different organs I found 

 croupous nephritis only seven times. In bodies, on the contrary, 

 in which tuberculosis was the cause of death, I have never failed in 

 finding catarrhal nephritis. I am far from connecting nephritis 

 in causal relation with the tuberculosis of other organs. Catarrhal 

 nephritis almost invariably accompanies all severe acute and 

 chronic diseases f . i., croupous pneumonia, typhoid fever, small- 

 pox, pyaemia, chronic suppurative processes, etc. Besides, both 

 forms of nephritis may appear primarily with the well-known 

 symptoms, and in their severest forms lead to a fatal termination. 



THEORY OF TUBERCULOSIS. 



Anatomical Signs of the Tubercle. We must examine the char- 

 acteristics of the morbid process which are concerned in the 

 formation of tubercle : the features which are observed by the 

 naked eye, those brought to light by the microscope, and those 

 inferred from the views taken by different pathologists. In this 

 way we may obtain a definition of the tubercle. 



What are the characteristic features of tubercle ? 



Is it the nodular shape 1 Certainly not. We know of a num- 

 ber of diseases of the skin which are characterized by nodules, 

 such as lichen, milium, acne, etc., and all follicular furuncles are 

 at first nodular. We know that in catarrhal inflammation of the 

 mucous membranes nodular follicular swellings occur, which dis- 

 appear as soon as the inflammation subsides. Occasionally we 

 find, in corpses where there is no sign of tuberculosis, nodules 

 the size of a pin's point or a poppy-seed, in the peritoneal cover- 

 ing of the liver and spleen, and sometimes, also, in the pleura. 

 These are very firm, transparent, without an injected area, and 

 are located on slightly cloudy or unchanged bases. Their origin 

 is apparent to any one who has seen acute pleuritis, especially 

 in the neighborhood of peripheral pyaemic infarctions of the 

 lung, and acute peritonitis in its earliest stages f. i., in puer- 

 peral process. Further, we often encounter, chiefly at the free 



