THE CYLINDER, CONCAVES AND BEATER. 



cylinder speed for which a change in cylinder pulleys is 

 usually made. These are given elsewhere in this book. 

 MAIN CYLINDER PULLEYS. 



Ascertaining Cylinder Speed. The best way to as- 

 certain the speed is by means of a revolution counter, 

 but if one be not at hand, the speed may be found 

 by counting the number of times the main drive belt 

 goes around in a minute. To do this, multiply the re- 

 quired speed of the cylinder by the circumference of the 

 cylinder pulley in inches and divide by 12 to reduce to feet. 

 Dividing by the length of the belt in feet will give the re- 

 quired number of times belt should go around in a minute. 

 For example : If cylinder be a 2O-bar, its speed should be 



