WORKED BY STEAM. 



the frame by wedges. The butt to be sawn is supported on 

 carriages {in m), one on either side of the saw and both running 

 on a Hght tramway, on which it is firmly secured by iron dogs 



Fio. 304. 



{n n). Two pairs of removable grooved iron rollers (z z) above 

 and below the butt press it forwards against the saAv. As soon 

 as the butt has been sawn through it is removed by butt- 

 carriages in front of the saw, another butt is then brought up 



