SANITATION 



217 



f ectant, f ormaldehyd is more efficient for disinfectant purposes 

 for germs, while sulphur fumes is better for ridding the premises 

 of lice and other vermin. Certain insects, as flies, withstand 

 the formaldehyd gas. 



A complete disinfection of poultry yards and runs — ^that is, 

 a destruction of all germs and vermin — is hard to accomplish. 



In addition to germs and vermin there are eggs and embryos 

 (the latter very young worms) eliminated from the bowel in 



Fig. 96. — A portable poultry house. Note at a the sled runners, New York 

 State Exper. Sta. 



case of intestinal infestation, which contaminates the food and 

 water and so serves to infest other birds. 



It is well if the poultry house can be located on a fence-line 

 and the birds allowed to run in one field at a time, the other 

 field being cultivated, that is, a crop raised on it. The mov- 

 able poultry houses have been advocated by some. In this 

 type we note runners made of 2 by 8 inch oak pieces. This 



