movement admits steam to the cylinder,
CY, which raises the revolving chains or skids, which transfers the
stock sidewise to other live rollers as required.]

As the sawn boards fall off the log, they land on "live," that is,
revolving rollers, which carry them along at the rate of 200 to 250
feet a minute. Stops are provided farther along to stop the boards
wherever wanted, as at the edger, Fig. 43, or the slasher. From the
live rollers the boards are transferred automatically, Fig. 44, by
chains running at right angles to the rollers and brought within reach
of the edger man. About one-third of the boards of a log have rough
edges, and are called "waney." These must go thru the edger to make
their edges parallel. The edger man works with great speed. He sees at
once what can be made out of a board, places it in position and runs
it thru. From the edger the boards are carried to the trimmer, which
cuts the length. The lumberman's rule is to "cut so that you can cut
again." The so-called 16' logs are really 16' 6". The trimmer, Fig.
45, now trims these boards to 16' 1", so that if desired they can
still be cut again. The trimmer may be set to cut at any desired
length according to the specifications.

[Illustration: Fig. 45. Automatic Gang Lumber-Trimmer. It may be set
to cut automatically to any desired length.]

[Illustration: Fig. 46. Lumber Sorting Shed. Virginia, Minnesota.]

[Illustration: Fig. 47.]

The boards are now graded as to quality into No. 1, No. 2, etc., Fig.
46, and run out of the mill, to be stacked up in piles, Fig. 47. Big
timbers go directly from the saw on the rolls to the back end of the
mill, where the first end is trimmed by a butting-saw or cut-off-saw
which swings, Fig. 48. The timber is then shoved along on dead rolls
and the last end trimmed by the butting-saw to a definite length as
specified, and shoved out.

One of the most remarkable features of the modern mill is its speed.
From the time the log appears till the last piece of it goes racing
out of the mill, hardly more than a minute may have elapsed.

[Illustration: Fig. 48. Cut-off-Saw. This saw trims the ends of
timbers.]

A large part of the problem of sawmilling is the disposal of the
waste. The first of these is the sawdust. In all first class mills,
this together with shavings (if a planing-mill is combined) is burned
for fuel. It is sucked up from the machines and carried in large tubes
to the boiler-room and there is