216 PRINCIPLES OF VETERINARY SCIENCE 



the ideal agent to employ. Cremation in the field of the car- 

 casses and excreta of animals that have died from an infec- 

 tious disease, is carried out by digging two trenches at right 

 angles to each other in the shape of a + (Fig. 61). Each trench 

 is 7 feet long, about 15 inches wide, and 18 inches 

 deep at the center, where the two meet, becoming shallower at 

 the ends. The earth is thrown into the angles at aa. Two or 

 three pieces of railroad rail or similar iron are placed across the 

 trench for the body to rest on and to allow the air to circulate 

 beneath the fire. Unless the animal has died from anthrax, 

 a disease of man contracted from animals, it will be best to 

 eviscerate the body and remove the limbs. Dry wood is laid 

 on the grates. The body is placed on this wood, then another 

 layer of wood, followed by the limbs, on the top of which the 

 viscera are laid. By this method it is possible to consume the 

 carcass of even a large animal in five or six hours. A few gallons 

 of kerosene sprinkled over the material will facilitate burning. 



Cold is less effective than heat as a disinfectant. In the north- 

 ern states, where the winters are long and rigorous, most disease- 

 producing microorganisms are unable to survive unless protected 

 in manure piles and other places secluded from frosts. In some 

 outbreaks of infectious diseases it has been observed that there 

 is a tendency for them to "die out" in the winter. The action 

 of cold is often accountable for this desirable turn, but too much 

 confidence should not be placed in it, as certain spore-forming 

 organisms like that of anthrax are not killed, besides there are 

 many chances of introducing a fresh infection. 



Chemical disinfectants are most commonly used about the 

 farm because they are easiest to apply. Those that are the least 

 poisonous to animals should be selected for direct application 

 when the body is to be disinfected. It is impossible to state 

 which is best, for the nature of the substance to be acted upon 

 must be considered. Bichlorid of mercury, commonly called 

 corrosive sublimate, is in favor with many. It has the power 

 to destroy all forms of microbes in relatively weak solutions. 

 It is a cheap, reliable, and easily handled disinfectant, but has 

 the disadvantage of being very corrosive and extremely poison- 

 ous. Carbolic acid is commonly employed in a 5 per cent, 

 solution in water. It does not injure clothing, metals, or wood, 

 and does not coagulate albumen so readily as bichlorid of mercury. 



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