Contagious and Epizootic Diseases. 51 



ducts, be carried to the kidneys, skin, bowels, etc., and 

 thrown out of the system in a few days or weeks, so that 

 the system would be no longer protected by them against 

 a new attack. But aside from this, as seen under our last 

 heading, a soup made of the tissues of an animal which has 

 been protected by a first attack of a given disease will 

 readily support the life, growth, and reproduction of the 

 germ which is the cause of that disease. This is conclusive ; 

 for the infusion of the tissues will contain the chemical pro- 

 ducts which were the alleged cause of the destruction of 

 the germ. 



c. The Condensation and Filtration Theoi'y. Tons- 

 saint found that during an attack of anthrax the lymphatic 

 glands were congested and swollen, and that on the sub- 

 sidence of the disorder the exuded matter wliich caused 

 the swelling, developing into fibrous tissue, contracted upon 

 the lymphatic ducts in such glands, compressing them and 

 lessening their calibre, so that he supposed they no longer 

 admitted the passage of the germs (bacteria) of the disease. 

 This view was thought to be supported by the absence of ■ 

 bacteria in the foetus in many instances where the dam had 

 perished from the disease, the filtration having presumably 

 been effected by the placenta. But, as I have shown else- 

 where, the foetus partakes of the nature of carnivorous ani- 

 mals which are insusceptible to many germs producing disease 

 in the herbivora. The filtration theory becomes untenable 

 when we consider that the lymph-corpuscles, which are in- 

 comparably larger than any lethal bacteria, continue to find 

 their way through the constricted tnbes of the glands, so 

 that there can be no insuperable obstacle to the passage of 

 the germs as well. Again, this condensation of the glands 

 would not prevent the development of a local anthrax sore 

 in the skin in the seat of inoculation, yet a first attack usu- 

 ally prevents the subsequent formation of the local disease 

 as well as of the general infection. The resistance to the 



