ted upon that
would not stand this part of the operation, such as fibers and a
number of pulverized materials. One of the jars was packed in tight,
nearly half full of cotton, and the other left entirely empty. The
question now is to measure the volume of cotton without bringing any
of the fibers in contact with the water. The liquid is poured into the
tunnel in the upright tube under head enough to partially fill the
jars when the overflow that stands on a level with the line, D E, is
open to allow the air in each jar to adjust itself as the straight
portions are wanted to work from. The overflow is then closed and head
enough of water put on to compress the air in the empty jar down into
half its volume. It may take a pipe long enough to reach up into the
second story, but it need not be a large one, and pipes round a cotton
mill are plentiful. In the jar containing cotton the water has not
risen so high, there being not so much air to compress, and comes to
rest on the line, C. Now we have this simple condition to work from.
If the water has risen so as to occupy half of the space that has been
taken up by the amount of air in one jar, it must have done the same
in the other, and if it could have been carried to twice the extent in
volume would reach the bottom of the jar in the one containing nothing
but air, and to the line, H I, in the jar containing cotton.

The fibers then must have had an amount of material substance about
them to fill the remaining space entirely full, so that a particle of
air could not be taken into account anywhere. The cotton has produced
the same effect that a solid substance would do if it just filled the
space shown above the line, H I, for the water has risen into half the
space that is left below it. This enables an overseer to look into the
material substance of textile fibers by bringing into use the
elasticity of atmospheric air, reserving the liquid process for
measuring volume to govern the amount of compressibility.--_Boston
Journal of Commerce._

* * * * *

VOLUTE DOUBLE DISTILLING CONDENSER.

This distiller and condenser which we illustrate has been designed,
says _Engineering_, for the purpose of obtaining fresh water from sea
water. It is very compact, and the various details in connection with
it may be described as follows: Steam from the boiler is admitted into
the evaporator through a reducing valve at a pressure of about 60 lb.