14 
BULLETIN 322, U. S. DEPARTMENT OF AGRICULTURE. 
a 10-pound washing and beating engine; and a wet machine capable 
of producing board sheets 15 by 22 inches. 
After several preliminar}^ tests on the small machines it was found 
that flax straw bleached with 14 per cent of lime for 15 hours at 170° 
C. and washed and beaten in the regular manner made a board which 
was almost invariably too hard and brittle, but if used with an equal 
amount of bleached old mixed string and an equal amount of bleached 
board cuttings a satisfactory board could be made. Still there was 
usually a little too much brittleness. 
Test No. 115. — A test was then made, designated as Xo. 115, using 
the large beater and wet machine. Two charges of 255 pounds each 
were made in a rotary pulp boiler, bleaching with 14 per cent of 
burned lime at 170° C. for 15 hours. About 275 pounds, dry weight. 
Fig. 4. — Fiber-board press or calender. 
of this stock was charged into a 700-pound beater and washed and 
beaten with a hard brush for 2\ hours, after which the roll was raised 
and the washing continued one hour longer. The wood was reduced 
and removed to a considerable extent, and, although the bast fiber 
was reduced in length somewhat, there was no bast-fiber loss in the 
wash water. At this point the workmen pronounced the stock very 
similar in appearance and action to that from flax waste. 
The washed flax was then added to a beater containing an equal 
weight of bleached mixed strings, which had been washed and beaten 
for seven hours, and an equal weight of bleached board cuttings was 
added. The furnish therefore was one-third mixed strings, one-third 
flax straw, and one-third board cuttings. This charge was beaten 
down, sized, and loaded by the experienced beatermen of the com- 
pany in the equh T alent of 12 hours total time. The stock was run 
into board on a regular 41-inch wet machine and dried in the loft 
