THE BABCOCK TEST 



39 



in which the test-bottles are placed. When at rest, 

 the pockets hang down, permitting the bottles to 

 stand upright. When the disc is in motion the pock- 

 ets swing out, carrying the bottles to a horizontal posi- 

 tion, the necks of the bottles being directed in toward 

 the center. The testers should be made to carry an even 



FIG. l6 — SMALL HAND-TESTER 



number of bottles. The steam-turbine tester is the 

 best form of centrifugal for factory work. It has the 

 advantage of maintaining a uniform rate of speed 

 and, in addition, the contents of the bottles are kept 

 hot, and hot water is supplied. In some forms, in 

 which the exhaust steam is not carried away and in 

 which no dampers are provided in the cover, the steam 

 testers may heat the fat too high. For use on farms, 

 hand-testers are available. It is always necessary that 

 the tester should be securely fastened to a firm founda- 

 tion and so set that the revolving disc is level. The 



