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probable cost of $7.00 per thousand feet The lumber was well manu- 
factured and there was very little waste, since almost everything could 
be utilized either for riprap lumber for the mines, or for cap-pieces, made 
out of the slabs. Six men were employed around this mill and wages ran 
from $3.00 to $5.00 per day. To run such a mill there would be required 
a sawyer, an engineer, a setter, one slab sawyer, an off-bearer, and a man 
to take away sawdust. After the logs had been taken out of the trees, 
other crews went in to make ties and mine props out of the tops, for which 
they were paid by the piece. It is the custom in some places to go through 
and take out the young white oak trees for legs and cross-bars, as it is 
claimed that such trees will be badly damaged by felling the large timber. 
All species were being cut in this operation and the average tree would 
yield not far from 100 board feet. We are indebted to Mr. Charles W. 
Weaver, superintendent of operations, for the many courtesies extended 
to us—following the felling crews and making stem analyses of trees, 
getting information about prices, etc., etc. 
Log rule—The official rule for scaling logs in the state of Illinois 
is the Doyle-Scribner rule, which Chapman calls a hybrid or combination 
log-rule. The straight Doyle rule is based upon a rule of thumb which is 
supposed to make certain deductions for saw kerf and slabbing of the log, 
and reads: ‘Deduct 4 inches from the diameter of the log at the small 
end as an allowance for slab. Square one-quarter of the remainder and 
multiply by the length of the log in feet.” For logs 16 feet in length this 
resolves itself into deducting 4 inches from the diameter at the small end 
and squaring the remainder, this giving the contents by the Doyle rule. 
For example, a 16-foot log 12 inches at the top end inside the bark would 
have a content of 64 board feet. This makes it very easy to apply as a 
rule of thumb, but for small diameters it gives very low results as com- 
pared with some other log rules—about half as much as the Vermont rule 
for an 8-inch iog, the Doyle giving only 16 board feet where the Vermont 
gives 40 board feet. For large logs the Doyle rule gave large results, so 
for logs 28 inches and over the Scribner rule values were taken and the 
combined rule was known as the Doyle-Scribner. The Forest Products 
Laboratory, Madison, Wisconsin, in commenting upon various log rules 
after an exhaustive study, says: “A combined Doyle-Scribnér rule, using 
Doyle on logs up to 28 inches in diameter and Scribner for logs 28 inches 
and over gives the largest possible overrun for both large and small logs.” 
The term “overrun” means the amount by which the mill tally of lumber 
sawed exceeds the scaled contents of the logs on the log deck or in the 
woods. So far as we have investigated the subject in this region the 
overrun given by the Doyle-Scribner rule is from 20% to 25%, varying of 
course with the size and soundness of the logs and the degree of utilization 
practiced by the operator or in the region. 
