UTILIZATION OF DOGWOOD AND PERSIMMON 29 
Where experience has shown that this occurs, water-resistant casein 
glues may be used. Good casein glues have high strength and will 
successfully resist dampness for a long time. They are, however, 
usually harder than animal glue and are liable to cause trouble by 
dulling the knives of wood-working machines in the shuttle factory. 
WASTE IN MANUFACTURE 
In order to manufacture 1,989,000 dogwood and persimmon shut- 
tles for domestic use in 1923, it was necessary to purchase 2,245,000 
shuttle blocks. This loss of 256,000 blocks, or 11 per cent, represents 
the discards thrown out because of defects developed in seasoning or 
revealed in making the shuttles. 
The loss was higher in dogwood blocks than in persimmon blocks, 
because of the more defective character of dogwood. From 1,790,- 
000 dogwood blocks 1,556,000 shuttles were made, with a loss of ap- 
proximately 13 per cent, while from 455,000 persimmon blocks 433,- 
000 shuttles were made, with a loss of less than 5 per cent. 
In the manufacture of approximately 11,000 boxwood shuttles from 
thick boxwood lumber, the percentage of waste was greater than in 
dogwood. 
The shuttle manufacturer finds it difficult to sell his accumulation 
of waste blocks, although they are generally uniform in size, well 
seasoned, and available for quick shipment. Manufacturers of 
small wood products such as chisel, awl, and knife handles, requir- 
ing strong, hard, and dense woods, will find shuttle manufacturers 
glad to dispose of this material rather than to burn it for fuel. It 
is generally more uniform in size and better seasoned than the waste 
which accumulates at the rough block mills in the South and is in 
excellent condition for the articles mentioned. 
The high loss of shuttle blocks in the manufacture of shuttles is 
not altogether necessary. Certain users of shuttles demand that the 
wood in the shuttles they order be absolutely perfect. They will 
not permit the slightest defect in the wood of the completed shuttle, 
regardless of whether that defect will cause loom interruptions or 
not. Small knots present in some parts of the finished shuttle 
where they would cause no interruptions are not admitted. Shuttle 
users who appreciate more the increasing scarcity of good dogwood 
will not demand a shuttle the wood of which is absolutely perfect, 
when the defects are so small as not in any way to hinder the proper 
operation of the shuttle. 
PRODUCTS OTHER THAN SHUTTLES 
SPOOL AND BOBBIN HEADS 
The heads of many thousands of spools and bobbins (fig. 19) 
are made of dogwood. The barrels of spools are generally made of 
less expensive materials, such as beech, birch, and maple. For the 
heads of spools and bobbins, however, which are liable to split and 
break when dropped, no other native wood is superior to dogwood. 
In making heads for spools and bobbins, the ends of the rough 
dogwood bolts are sawed off, the thickness depending upon the thick- 
ness of the desired head and the diameter upon the size of the ma- 
terial available. The sections cut off are then turned individually 
