142 



VOLUMETRIC AND INDIRECT ESTIMATION OF PAT. 



* S A 



is held in the right hand and the loose end in the left. The cord 

 is pulled with the right hand, just sufficient tension being kept 

 on the end with the left to make it bite. At the end of the 



stroke, the left hand is 

 brought up near the machine 

 to loosen the cord round the 

 spindle, otherwise there is 

 danger of the cord winding 

 up. 



The cord is now pulled 

 back with the left hand 

 keeping it quite loose i.e., 

 letting the right hand go back 

 quite freely. The pulling 

 with the right hand is re- 

 peated, and continued till 

 the speed is high enough. 



It is advisable to stop up 

 the hole in the spindle, as it 

 causes the cord to wear. 

 Should the cord wear out 

 and break, it can be replaced 

 easily at an infinitesimal 

 cost . This method of driving 

 was worked out in the 

 author's laboratory by 

 Boseley and Hosier. 



The Lister Machine. 

 This has practically the same 

 form as the Gaertner- 

 Hugershoff machine, but does 

 not include the " Excelsior " 

 or" Rapid " gearings, which 

 are covered by patents. The 

 frame is of different con- 

 struction, and is S-shaped. 

 Round the spindle a small 

 brass pulley is fixed * (in the 

 24-bottle machine a ratchet 

 is added), and it is driven 

 by a string wound round 

 this by Boseley and Rosiers 



I = 



Figs. 19 and 20. Gerber Bottles. 



method, which, however, was independently applied by Lister. 



* In practice it is better to take off the pulley, stop up the hole, and 

 drive on the spindle direct. The machines have also been made without 

 the pulley. 



