proportion of bast
fiber in the total shipment of 4 tons, although two hand separations of
small representative samples gave results averaging 8 per cent. The
chemical character of the material was such and the quantity was so
small that any appreciable variation of the proportion should not affect
materially the treating processes finally adopted, yet its presence in
varying proportions undoubtedly would modify to some extent the quality
of the resulting paper product. Since the length of the ultimate bast
fiber averages about 22 mm. and the length of the ultimate hemp wood
fiber averages 0.7 mm., it is natural to assume that the bast fiber
would tend to increase the strength of paper produced from the hurds.
(Fig. 4.)
[Illustration: FIG. 4.--Fiber derived from the woody portion of the
hurds. x75. From a microphotograph.]
The broken pieces of wood contained in the hurds varied in length from
mere particles which were somewhat finer than sawdust to pieces about
3-1/2 inches long, exceptional pieces being found which measured 6
inches in length. The majority of the long pieces were between 2 and 3
inches in length. In thickness the pieces ranged from one-eighth of an
inch, in case they were derived from the base of the hemp stalks, to
about one sixty-fourth of an inch in those pieces which were derived
from the top and branches of the stalks. In cross section the pieces
often were found to be a quarter or half of the rounded rectangular
woody shell of the stalk, although there appeared to be no regularity in
this respect.
From the pulp-maker's standpoint the great irregularity in thickness,
length, and mass of the woody pieces militates decidedly against economy
in pulp production. The smaller pieces reduce by chemical treatment
sooner than the larger fragments and are thereby overtreated, which
results in a lower yield of cellulose fiber and a product composed of
undertreated and overtreated fibers, the production and use of which are
not satisfactory or economical. It probably would be found more
satisfactory, therefore, to screen or sort the hurds and treat the
various sizes separately and differently.
Associated with the hurds was a small quantity of chaff and dirt,
composed chiefly of sand, soil, particles of hemp leaves and flowers,
and other extraneous matter. The sand and soil were present because of
the practice of placing the stalks in shocks in the field, the butts of
the stalks being in contact wit
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