484 AUXILIARY FOREST INDUSTRIES. 



German State forests, with few exceptions, been decided in 

 favour of the latter alternative. The State should not, how- 

 ever, hesitate to favour and support sawmills, as its interest 

 lies clearly in that direction. As, moreover, sawmills are 

 controlled sometimes by forest-owners, especially private 

 owners of large forests, and it is desirable that foresters 

 should possess some knowledge of their mode of construction 

 and management, a general account of them is included in this 

 book. 



(a) Forest Sawmills. 



1. Description. 



The ordinary forest sawmill is characterised by its position 

 in a forest, its usually simple mode of construction, by being 

 driven by water-power and having as a rule only one blade to 

 a saw. It consists of three parts, the frame which moves up 

 and down with the saw, the travelling or butt carriage sup- 

 porting the logs, which are to be sawn, and mechanism for 

 setting both the above in motion. 



The saw-blade a (Figs. 296, 297), is nearly vertical and fixed 

 in the frame bb, moving up and down with it between the 

 wooden slides ee ; below the frame is a pitman /, which is 

 attached to a crank g. Every revolution of the wheel B drives 

 the saw up-and-down by means of g. The cut is effected by 

 the downward stroke of the saw, the steep edges of the teeth 

 being pointed downwards. During the upward stroke, the butt 

 to be cut must be pushed forward against the saw. With this 

 object, the butt is placed on the carriage h, which consists of a 

 long, somewhat narrow, strong platform. The head-blocks P 

 and Fare dovetailed into the carriage at each of its extremities 

 and serve to hold the butt in position. The carriage is 

 pushed forward by means of a rack n, which is driven by the 

 pinion k of the cog-wheel L and the latter by the cog-wheel M, 

 on the axle of which another cog-wheel N is fixed and driven 

 by the ratchet q ; q is connected by a hinge with one of the 

 levers rr attached to a cylinder ?/, which is moved through part 

 of a rotation, and back again, by the motion of the other 

 lever r attached to the upper part b of the saw -inline. 



