the pulp from the last chest, delivers it into a pipe,
h, by which it may be conveyed to any desired
point, the said pulp having been sufficiently bleached
before arriving at the said pipe,
h. It
will be seen that by these means all the pulp is thoroughly
and uniformly subjected to the bleaching agent and
that the bleaching is gradually performed in all parts
of the pulp, which is first acted upon by the weaker
bleaching agent that has previously operated upon the
pulp before treated, and that finally, when nearly
bleached, the pulp is acted upon by the bleaching
material of full strength, this action being far more
efficient than when the materials are simply mixed
together, the unbleached material with the strong
bleaching agent, and allowed to remain together until
the bleaching operation is finished, in which plan
the bleaching agent loses its strength as the bleaching
operation approaches completion, so that when the
pulp is nearly bleached it is operated upon by a very
weak bleaching agent. By having the pulp transferred
from one chest to the next in the reverse order to
that in which the liquid is transferred it will be
seen that all parts of the pulp are acted upon uniformly
and equally and that the operation may go on continuously
for an indefinite period of time without necessitating
stopping to empty the vats, as is the case when the
liquor only is transferred from one vat to the next.
A pump may be used for lifting the bleaching liquid,
as shown, for example, at
k, Fig. 1. where
said pump is used to raise the liquid delivered from
the chest,
a2, and discharge it into the trough,
m, by which the pulp is carried to the inlet
pipe,
b. By the use of the pump,
h,
a stronger flow of the liquid into the pipe
b,
of the first chest,
a, is effected than if
it were taken directly from the washer of the chest,
a2, which is desirable, as the pulp is delivered
in the trough,
m, with but little moisture.
It is obvious that the construction of the apparatus
may be varied considerably without materially changing
the essential features of operation. For example,
the washers might be dispensed with and the liquid
permitted to flow through suitable strainers from one
chest to the next in order, by gravity, the successive
chests in the order of the passage of the pulp being
placed each at a higher level than the preceding one,
and it is also obvious that the construction of the
pulp conveyors might be widely varied, it being essential
only that means should be provided for removing the
pulp from one chest and delivering it into the next
while carrying only a small amount of the liquid from
one chest to the next with the pulp.
* * * *
*
BEING A NEW SYSTEM OF CEREBRO-SPINAL THERAPEUTICS.