408 



FOODS AND FOOD ADULTERANTS. 



In this figure is represented the type of apparatus used for rendering 

 lard, etc., under pressure. The rendering vessel is made of boiler iron 

 or steel, and varies in size according to the magnitude of the establish- 



ment. A very common size is 10 to 12 feet in length and 3 to 5 feet in 

 diameter. The heads, scraps, and other materials are put in at M. 

 When the tank is full M is closed. Steam is admitted through the pipe 

 thus marked, and condensed water drawn oil* through the water-pipe. 

 Through the cocks at D the depth of lard in the taiik can be determined 



