Equipment 385 



the coldness of the material. As sometimes constructed, 

 they are also slippery, but this need not be the case, 

 as a rough finish will obviate this difficulty. The coldness 

 may be avoided either by the liberal use of bedding or 

 by an overlay, which consists of a board platform laid over 

 that part of the cement floor on which the pigs are to 

 lie and the bedding placed on top of this. In summer, of 

 course, this platform should be removed and the pigs 

 allowed to lie on the cool floor. Some persons have 

 recommended two layers of coal tar between the grouting 

 and surface layers of cement. In winter, moisture some- 

 times accumulates under the platform, so that it will 

 need to be moved from time to time, but if the dust is 

 kept from beneath it, very little dampness will accumulate. 

 Those who have used concrete floors differ in their judg- 

 ment on them. Some maintain that the pigs warm the 

 concrete floor through their bedding, and the floors re- 

 main warm, provided they are dry. On the other hand, 

 others maintain that the floors are always cold and clammy, 

 and must make the pigs uncomfortable. Undoubtedly 

 the drainage and ventilation of the building have much 

 to do with the condition of the concrete floor. If the 

 ventilation is not good, more moisture will accumulate 

 on the floors; and if drainage is poor, they will like- 

 wise be damp. If ventilation and drainage are good, 

 however, keeping the floors dry is a much easier problem, 

 especially if the floors are thoroughly water-proof, which 

 will not be the case unless the concrete is made from the 

 correct mixture and properly tamped. 



DIPPING VAT 



In order to keep pigs free from external vermin and 

 occasional attacks of mange, some system of dipping is 

 2c 



