HOG CHOLERA. 1275 



lesion with inflamed, swelled, or congested borders — for instance, in a 

 wound caused by ringing or castration, etc. — the morbid process is sure 

 to develop in the inflamed or congested borders of that wound. All this 

 is easily accounted for if the bacilli and their germs constitute the infec- 

 tious principle, and if the mode and manner in which they obstruct and 

 <^log the capillary vessels is taken into consideration; but it is utterly 

 irreconcilable with the non-appearance of any local reaction after an 

 inoculation by means of a wound too slight to cause congestion, if the 

 infectious principle possesses the nature of a virus, or of a chemical 



agency. 



rv. Frost and the Virus. 



Swine plague, until the last days of December, or until the ground 

 becomes covered with snow, and the weather exceedingly cold, was 

 s[)reading from farm to farm and from place to place, in the locality vis- 

 ited, but as soon as the temperature began to remain below tlie freezing 

 point at noon as well as at night, it at once ceased to spread from one 

 farm or locality to another. At the same time, however, it was observed 

 that the very cold weather of the last days of December and the first 

 days of January did not materially interfere Avith the spreading of the 

 swine plague from one animal to another in all pens and hog lots in 

 which the disease had previously made its appearance, and in Avhich the 

 way of feeding and watering the animals was such as to allow a contam- 

 ination of the food and the water for drinking with the excreta of the 

 diseased hog, or in which the pigs and hogs still healthy had open 

 wounds, sores, or scratches, and had to sleep together with the diseased 

 hog in the same place and on the same litter. Afterwards, when milder 

 weather had set in, the spreading from one place to another very slowly 

 commenced as^ain. (The cold indicated 20 degrees below zero.) 

 V. Measures of Preventive. 



In relation to the spread of the disease and measures for prevention, 

 Dr. Detmers advises as follows: 



The most effective means of prevention that can be applied by the in- 

 dividual owners of swine consists, first, iii promi)tly destroying and bury- 

 ing sufficiently deep and out of the way the first animal or animals that 

 show symptoms of swine plague, if the disease is just making its appear- 

 ance, and in aismfecting the premises, or if that is difficult, in removing 

 the herd at once to a non-infected place, or out of the reach of the infec« 

 tious principle. If possible the herd should be taken to a piece of high 

 and dry ground, free from any straw and rubbish — if recently plowed, still 

 l)etter — and should there receive clean food and no water excei)t such as 

 is freshly drawn from a well. If this is complied with, and if all com- 



