74 FOREST commissioner's REPORT. 



of August 4-foot bolts arc entirely stained. Soon after this 

 white streaks begin to appear in the wood and it loses it strength. 

 Whole stems left in the woods stain for only 2 or 3 feet at both 

 ends, but the rest of the material is not so clean and white as 

 when winter-sawed during the first season. Best results are 

 obtained by sawing the wood while it is frozen. 



With clear, white birch of the best quality, practically free 

 from large knots and red heart, 2 cords of round logs yield a 

 thousand board feet of spool bars. With the ordinary run of 

 material, however, it takes from 2^. to 3 cords to make a thou- 

 sand feet of bars. Exceptionally poor material, practically culls, 

 has been known to run 6 cords to the thousand feet of bars. 

 The sawing of the logs into such small bars makes much saw- 

 dust waste, and half a cord of sawdust has actually come from 

 a single cord of bolts. 



Immediately after sawing, the green bars are stacked in open 

 piles out of doors, but under cover. The air has free access to 

 them, and they usually season for several months. W^hen it is 

 desired to use them, they are put into a dry kiln to complete the 

 seasoning. It is essential that seasoning should be thorough, 

 since the slightest change in the size of the spool after manu- 

 facture makes it impossible for the delicately adjusted machines 

 now in use in the cotton mills to wind the thread upon it. 



The manufacture of the kiln-dried bars into spools dififers 

 slightW in various mills, though the general process is the same. 

 The bars are first cut into short pieces the exact length of the 

 .spool desired, and these are then put through a lathe which 

 turns out the spools ; in many cases these spool machines are 

 entirely automatic. The best of them work with great speed 

 and accuracy and turn out spools at the rate of one a second. 



At this stage the spools are still rough and must be smoothed 

 off so that the thread may not be cut and broken in winding. 

 This smoothing is done by rolling the spools about for half an 

 liour or more, together with several balls of wax or paraffin, in 

 a large, hollow cylinder. This is the general process by which 

 the ordinary sewing spools are made, and they are then sorted, 

 culled, and shipped. 



The very large .spools, however, must be made in three pieces. 

 A cylindrical ])iece several inches long and threaded at each end 

 serves as the body of tlie spool, and the heads are cylindrical 



