352 ARTIFICIAL BROODING 
These units are heated by kerosene lamps (Fig. 165). The 
usual method is to maintain a uniform temperature ia the 
Fic. 165.—Portable indoor hovers make it possible to use the laying houses for brooding 
purposes. (Photo by Rancocas Poultry Farm.) 
Fia. 166.—Small portable outdoor brooders heated by kerosene lamps. 
brooder house by the use of a few coils of hot-water pipe and then 
to increase the hover temperature to any desired degree by the 
