consumption, after which the chips are sorted by sieving, the large
pieces being rechipped. There would be a noteworthy difference in the
installation, operating, and depreciation costs of the two equipments,
and this difference would counterbalance to a considerable extent the
difference in cost of raw material storage.

It is possible that in the use of the chip loft more care would have to
be exercised in using hurds because of the tendency of the bast fiber to
cause lodgments, but this should not be considered a serious difficulty.

The weight of hurds which are capable of being charged into a rotary is
a decidedly unfavorable factor. The weight of a cubic foot of hurds
varies somewhat with the proportion of bast fiber, but averages about
5.4 pounds, which, compared with a cubic foot of poplar chips at 8.93
pounds, represents a digester charge of 60.5 per cent of the weight of
a poplar-wood charge, or, in terms of fiber capacity, the hurds charge
would yield 38.6 per cent as much fiber as the wood charge. The hurds
upon being baled for transportation may be broken and crushed to such a
degree that the weight of the charge may be increased, and it might be
found possible to increase the charge weight by steaming or by the
employment of tamping devices. This small weight of charge constitutes
one of the most serious objections to the use of hurds in paper
manufacture.

In those tests in which the most satisfactory results were obtained, the
cooking conditions were 29.5 per cent of caustic soda at a concentration
of 107 grams per liter and a causticity of 84.0 per cent acting at a
temperature of 170 deg. C. for five hours, or a total time of seven hours.
The steam condensation in the rotary used for these tests was abnormally
high, due to the fact that the steam supply pipe was uncovered for a
considerable distance and the rotary was entirely uncovered. It is
believed, therefore, that a larger amount of caustic was necessary than
would otherwise have been the case. This belief is strengthened by the
quality of the waste liquor from one of the later cooks, which gave on
analysis 16.85 grams per liter of free caustic soda and showed a
causticity of 27.75 per cent. These data show that only 67.3 per cent of
the total caustic employed was actually consumed in the cooking
operation, which percentage is lower than obtains in practice. The stock
from this cook was bleached with 11.5 per cent of bleach. But even as
the figur