es stand, the comparison with poplar cooking practice is as
follows: 29.5 per cent caustic soda used as against 22 to 25 per cent;
107 grams per liter as against 100 to 110; 84 per cent causticity is
little different than obtains in practice; 170 deg. C. is about commercial
practice; five hours at pressure as against four to six hours; seven
hours' total time as against possibly six to eight hours; 11.5 per cent
bleach as against 8 to 10 per cent. Thus, it is evident that the cooking
conditions employed were slightly more severe and expensive than those
in commercial use with poplar wood.

The yield of total fiber obtained from the hurds may be placed at 35 per
cent of bone-dry fiber calculated on the bone-dry weight of hurds used,
or 33.1 per cent of air-dry fiber calculated on air-dry hurds. The yield
of bleached fiber was not determined in this preliminary work, but may
be safely estimated as 30 per cent, which is low when compared with a
yield of about 47 per cent of bone-dry bleached fiber from bone-dry
poplar wood. It is believed quite possible that satisfactory cooking
conditions may be found which will give a higher yield than was obtained
during these tests. The stock should be classed as easy bleaching, and
11.4 per cent of bleach is a satisfactory figure, although a little
high.

As to beating cost, in the last two and most satisfactory tests the
total washing and beating time was three hours, which may be about an
hour more than ordinarily is used in making papers of this grade,
although the practice varies to a considerable extent.

In regard to furnish, there is such a diversity of practice that it is
difficult to make a comparison, but if the hurd stock can be produced as
cheaply as soda-poplar stock, the furnish used in these last two tests
should be regarded as satisfactory to the book and printing paper
manufacturer.

The finish of the paper was not all that might be desired, but that was
due almost entirely to the calender stack available for the work, which
was composed of nine light rolls, many of which were about 6 inches in
diameter and which had not been reground for some time. From a small
test on a large calender stack it was readily shown that the paper
produced is capable of taking a satisfactory finish.

This comparison, satisfactory in many respects, develops two factors
which are decidedly unfavorable to hemp hurds, namely, raw-material
storage and digester capacity, and they must be