104 VITALITY AND EFFICIENCY WITH RESTRICTED DIET. 



wind chest, A, shown in detail in figure 9. In the top of this wind 

 chest are three openings. At the extreme right there is an opening, B, 

 figure 9, provided with a water seal into which caps of various sizes can 

 be set. The other two openings, each of 10 nun., lead directly into the 

 center of the bottom of two cylindrical copper cans, Ci and C2. These 

 openings were drilled in disks at the same time and hence are of 

 exactly the same size, which was subsequently proved by most careful 

 calipering. Each disk is attached with a threaded collar to a pipe in 



Fig. 9. — Detail of wind chest. 



A, wind chest; B, opening to outside. Ci, Ca, cylindrical copper cans from which air is drawn by 

 means of two Crowell blowers. R, hand hole; S, opening into wind chest for discharge from 

 rotary air-impeller; W, wire screen; p, petcock for attaching manometer to obtain pressure 

 in wind chest. 



the top of the wind chest. Between the 10-mm. disks and this pipe are 

 placed rubber gaskets, which insure tight closure. The details of this 

 installation are given in figure 10, in which a is the brass disk with a 10- 

 mm. orifice, h the collar, c the brass pipe soldered to the top of the wind 

 chest, and d the rubber gasket. To attach the cans Ci or Ct to the 

 top of the wind chest and secure an air-tight closure, a rubber gasket, e, 

 is placed between the can and the wind chest and pressure applied by a 

 threaded collar, /. 



