Omaha daily bee., 1895-09-22

moment of completion of the new apparatus,
will be turned into a large funnel connected
with a horizontal pipe several feet in
diameter and 152 feet long. A certain
quantity of air will be carried with this
water and the mixed contents, air and water,
will be discharged into the separator, as the
reservoir Is called, at the foot of the wall
rock, which is ten feet in diameter, ten feet
having a capacity of 1000 cubic
feet. That the air may be properly
distributed the pipe 1. tapered to a hyper
bolic curve to meet the varying veloclties of
falling bodies. From the separator are two
outlets, one for water, the other for air, the
pipe for the water outlet being nearly three
times as long as the pipe connecting with the
air output. At the same point at which
water is poured into the down or tapered
pipe is a U-shaped pipe and against the face
of the wall rock presents a most instructive
lesson in hydraulics. Into the longer arm or
leg, as Mr.. Priestly calls 1t. of this U, is
forced the air from the separator, thereby
pumping water as in the numerous air-lift
pumps which are extensively used, not only
in placer mining and irrigation, but for lift
ing water out of flooded mines.
A REVELATION IN HYDRAULICS.
There is not so much in the mere detail of
this plant that is interesting and instructive
TO the layman, although there is not a single
working valve or joint in the whole series of
pipes, but in the absolutely new idea as to
49, A'HN ''' 'NNNANJ - 'SpfN NHNs
the chief interest centers.
In a conversation with Mr.. Prlestly he said
as to this most important discovery: AFTER
much thought l came to the conclusion If |
could make air bubbles the exact size l
wanted them, l could lift water to almost any
height. | m closely all the books on
hydraulics and mechanics. but found none
that went into the consideration of bubbles In
relation to my plan of lifting the water. In
view Of the dearth of anything like scientific
investigation on the bubble question | went to
work to demonstrate my theory, taking a Sc
rles of glass tubes for my confined spaces and
a lake as my open space. After two years of
close study as to the phenomena Of bubbles |
arrived at the conclusion that a bubble nine
inches in diameter was the worst to contend
with and my course was open to avoid a pipe
that would create such a bubble, but would
make bubbles either larger or smaller than
nine inches. l asceptained that a nine-inch
bubble would rise in a glass tube at the rate
Of nine feet per second. In rising through
sixty-fve feet Of water it would take thirteen
seconds. A pipe twenty inches In diameter
represents about two and one-fourth cubic
feet Of air TO each foot Of water, and, carry
ing my theory still further, 1856 cubic feet OF
air must be placed into the pipe every thir-
teen seconds to lift the water TO the top OF
the chamber This would be without Y flow
Of any kind from the pipe. Having clearly
demonstrated this problem II is easily seen
that any excess Of air over the amount re-
quired to lift the column of water TO the top
VI Nut plPt viii Nadst II " AZ III
size Of the ~globules determining this result.
THE shorter leg in the U-shaped pipe,
which is so essential to the complete sue
cess Of my scheme, is sixty-ive feet. the
tongue leg is 1852 feet In the vertical. While
there are siXty-hve feet Of solid water in the
short leg, in the long leg the sixty-fve feet
Of water is scattered from top to bottom, the
remaining space being occupied with air. II
becomes absolutely necessary under these
conditions TO have an excess of sixty five feet
sufficient to give a velocity to Nhe water OF
five feet per second. The air being at Q
standstill any excess Of velocity Of five feet
will carry air in the separator tank an6
create the lifting force Necessary to force the
how."
VELOCITY OF BUBBLES.
But how did you arrive at a positive SO,
! luton as to the velocity OF bubbles? ?" l in
qulred.
while I have not formulated a rule tina
viii bear close inspection from n scientific
standpoint. siill l may say that the helgh
Of the water above the top OF the globul,
represents the pressure on the top OF tn,
bubble; the pressure on the bottom OF thu
bubble is represented by the height Of waite
] Nboye the bottom Of the bubble, the diamete.