the
influence on the mechanical properties of distance from the
pith, a 4-foot bolt will be cut from the top end of each 16-foot
butt log.

(_b_) For investigating the variation of properties with the
height of timber in the tree, all the logs from one average tree
will be used.

(_c_) For investigating the effect of drying the wood, the bolt
next below that provided for in (_a_) will be used in the case
of one tree from each locality.

_Marking and Grouping of Material_

The marking will be standard except as noted. Each log will be
considered a "piece." The piece numbers will be plainly marked
upon the butt end of each log by the collector. The north side
of each log will also be marked.

When only one bolt from a tree is used it will be designated by
the number of the log from which it is cut. Whenever more than
one bolt is taken from a tree, each 4-foot bolt or length of
trunk will be given a letter (mark), _a, b, c,_ etc., beginning
at the stump.

All bolts will be sawed into 2-1/2" X 2-1/2" sticks and the
sticks marked according to the sketch, Fig. 50. The letters _N,
E, S,_ and _W_ indicate the cardinal points when known; when
these are unknown, _H, K, L,_ and _M_ will be used. Thus, _N5,
K8, S7, M4_ are stick numbers, the letter being a part of the
stick number.

[Illustration: FIG. 50.--Method of cutting and marking test
specimens.]

Only straight-grained specimens, free from defects which will
affect their strength, will be tested.

_Care of Material_

No material will be kept in the bolt or log long enough to be
damaged or disfigured by checks, rot, or stains.

_Green material_: The material to be tested green will be kept
in a green state by being submerged in water until near the time
of test. It will then be surfaced, sawed to length, and stored
in damp sawdust at a temperature of 70 deg.F. (as nearly as
practicable) until time of test. Care should be taken to avoid
as much as possible the storage of green material in any form.

_Air-dry material_: The material to be air-dried will be cut
into sticks 2-1/2" X 2-1/2" X 4'. The ends of these sticks will
be paraffined to prevent checking. This material will be so
piled as to leave an air space of at least one-half inch on each
side of each stick, and in such a place that it will be
protected from sunshine, rain, snow, and moisture from the
ground. The sticks will be surfaced and cut to length just
previous to test.

_Order of Tes