146 DUPLEX OR EITHER-SIDE LATHE. 



the one hand, or rendered uselessly slack and of 

 insecure adaptation to the wheel, on the other. 

 ' I need scarcely to remark that, as the headstock is 

 suspended over the centre of the table, it is necessary 

 that the driving-wheel below should also be central. 



When this lathe is intended for the operating 

 room it will require but one treadle of the ordinary 

 kind, but when it is intended for the rougher and 

 harder usage of the work-room, it may be made 

 available for two persons occasionally to work with 

 it simultaneously. For this purpose two treadles, 

 hinged to the base, directly opposite each other, 

 should be adopted, their noses (if I may use the 

 term) just clearing each other under the crank. (See 

 drawing No. 2.) A strap made to embrace the crank, 

 and firmly riveted or tied around it, having its ends 

 fixed, one to each of the treadles, supplies the place 

 to each treadle of the iron hook in common use ; and 

 has the advantage of working smoothly and noise- 

 lessly. They can be worked separately or conjointly. 



It was my intention to have had one of these 

 lathes here this evening, in order that it might be 

 seen and examined, but unfortunately I have not 

 been able to find a machinist who would undertake 

 to make me one within any reasonable length of 

 time, or at least in time for this evening. 



Note, — The drawings referred to in the foregoing paper being unsuited 

 for this volume, I have had made a perspective drawing of the lathe, 

 which I think conveys a better general idea of its construction, and will 

 Jbe sufficient to render the above description intelligible. 



