DISEASES OF SWINE AND OTHER ANIMALS. 39 



C sliows plain symptoms of disease; its appetite is poor, and some 

 emaciation bas gradunlly taken place ; at least C lias not improved like 

 A, and weighs abont half as much as the latter, notwithstanding A is 

 in an open pen, exposed to the inclemencies of the weather, and in a 

 good, new building, with a shingled roof, in which it is amply protected 

 against the changes of the weather. 



October 17. — Pig C rather poor appetite ; breathing a little accelerated, 

 and coat of hair somewhat rough and staring. 



October 18. — Pig C exhibits plain sjonptoms of swine-plague; its 

 breatliing is accelerated; it sneezes a good deal, and its appetite is poor. 

 Eats some in the evening. 



October 19. — Pig improving; has better appetite. 



October 20. — Pig much improved ; eats its food again, but is not 

 greedy. 



October 21. — ISTo change. 



October 22. — Pig C is lively again, and eats well — at any rate, seems 

 to care more for its food. The sores on the ears are healing and disap- 

 pearing. 



October 23. — Pig C must be considered as fully recovered from its 

 slight attack. 



Up to date pig C has presented the appearance of a perfectly healthy 

 pig. Its ears have healed, and are now (November 11th) perfectly smooth. 

 It is lively and greedy for its food, but has grown very little, and weighs 

 to-day about half as much as pig A. It can be seen very iilainly that 

 pig C has been sick. When I received A, B, and C, A was slightly the 

 best pig. B came next, and C was the smallest, but the difference was 

 only a trifling one. 



The experiments just related show that the bacilli and their germs 

 must have a causal connection vrith the morbid process of swine-plague, 

 because an inoculation with bacilli and bacillus-germs, cultivated in such 

 an innocent and harmless fluid as milk, i)roduced the disease, while an 

 inoculation with blood-serum from diseased hmgs — a highly infectious 

 fluid, if not deprived of its bacilli and bacillus-germs — remained without 

 the sliglitest effect after it had been freed from its bacilli and bacillus- 

 germs. I know very Avell that the«result obtained can hardly be consid- 

 ered as conclusive, and that some more experiments of the same kind are 

 needed to conlirra the conclusions arrived at. 



5. THE CONTAGION, THE CAUSES, AND THE NATFEE OF THE MOEBID 



mocEss. 



That swine-plague is an infectious disease, whicli can be communi- 

 cated to heathy animals, has been demonstiated by my experiments. 

 It has further been proven that an exceedingly small quantity of an 

 infectious or contagious substance (blood-serum or exudation, for in- 

 stance) if inoculated, or directly absorbed by the A-ascular system, is 

 suihcient to produce the disease. It has also been ])roven tliat morbid 

 tissues and morbid products, if consumed by health^' pigs, will cause 

 them to become affected Avith the plague. Consequently, two ways of 

 infection have been ascertained with certainty. Further, if the results 

 of iha post-mortem examinations are inquired into more closely, it will 

 be found that the principal morbid changes have occurred in the digest- 

 ive canal, but especially in the cajcum and colon, in all those cases in 

 which the disease had been communicated by way of the digestive ap- 

 paratus ; and that, on the other hand, the i)rincipal scat of the morbid 

 process has been in the organs of respiration and circulation, or in the 



