State journal & flag., 1846-10-09
For The journal and Elne.

For the Journal and Flag.
UNIVERSITY OF ALABAMA, Ser. 81, 1916
SIR:
have read with interest, the article,
which you were SO kind TO point out 10 me
In the Cultlvator, on the subject of Mr.. T.
w. Ellsworth's .self.actng pump" Tc
your inquiries as TO the probable secret oil
its action, will endeavor to reply.
Mr.. Ellsworth describes his machine only
by saying that it is a sphon, which, by
means ofan apparatus attached, is forced
to deliver a portion of its water at the high.
est point. This can be explained only on
the suppostion that the lndescrbed appara.
tns embraces an application oil the principle
Of Montgol6ers hydraulic ram.
This remarkable machine is SO little
known in our country, that It may be well
to explain lis construction. Fo, simplicity,
suppose common eadcn tube, four or FIVE
feet long, 10 be secured in an inclined posi-.
ton, one end being about IA foot higher than
Inc other. Bend this higher extremity up
right, and solder to it funnel. Water ad
mitcd into this funnel, in such quantity as
to keep it nearly full, will flow out at the
lower end with velocity dependent on the
difference of level This water, received
against an obstacle outside the tube, would
exert but trivial force but should the
current be instanianeously arrested by the
sudden closing OF valve at the lowe. end,
The valve would receive blow MS if sol.
ID had struck it, with the weight of the
entire column, and moving just as fast
BY frightening the tube or increasing the
difference oflevtL or doing both these things
at once, this conclusion may be made more
and more violent, ill the tube will burst.
and I'LL notube whatever can be made strong
enough 10 endure the strain. But the inju.
rious effects of the shock may be prevented,
by the Use of what is called an air. chamber,
or condenser which is merely tight yes
sci containing air, and communicating
with the compressed water within the tube,
by means of valve opening inward. This
valve is lifted by the pressure, the water
rushes into the vessel, condenisng the air be.
fore it, and The strain is relieved The elias.
tic spring of the air will immed ately close
the valve, and prevent rehux. Water
thus confined under pressure, is in the si'-
uaiion Of that which is forced into the air
chamber OF fire engine. and will discharge
itself in a jet, in like msnn'r 1t only needs
that the operation just described should be
continually repeated, to keep up constant
discharge. Bend The lower extremity of
the tube upward, and whrr the shock is
over, the choke valve we have supposed 10
be placed there, will fall by lis own weight.
Then the flow through The tube will re.
commence, and will presently carry the
choke.vave along with it, stopping the
passage again and driving more water into
the air-chamber. And this, in substance,
is Montgolfer's waterman.
Ii the water, instead OF issuing in a et,
be allowed to ascend in an upright tube, it
may be forced 10 an immense height, by
very insignificant fall in the ram. The
driving column, however, should be long
In proportion TO the work it is expected TO
perform. Ewbank, in his Hydraulics. men,
lions machine of this kind, which, with
fall Of only four feet and half delivered
one hundred hogsheads of winter daily, a, an
elevation of one hundred and thirty four
feet. But though the driving column must
be long for such performances as this, il
need not be straight, provided the curves
are genllc. Ew5ank mentions another ram,
in which this column descended in spiral
tube entirely concealed within an ornamen
tai altar on the banks of the Rhine, and
delivered two thirds of the water flowing
through 1t, at castle situated several hum
drcd feet higher.
Thus the waterman, simple as it is in
construction, and almost without liability to
arrangements, may be made most valua-
BILE means Of irrigating lands, or supplying
water for stock or for household purposes
. to all persons living in the vicinity of small
streams which are not liable 10 extreme fuc.
tuations OF level. And TO those who have
not this advantage, but who have wells or
springs higher than the neighboring ravines
or valleys, the adaptation OF its principle to
the siphon will prove slmos. equally useful
This adaptation. in reply to your inqui.
ries, it is my present business 10 explain.
The driving force OF the ram. it will be
remembered, is The momentum of a confn-
ed column offluid. Now this momentum is
the same in given lube. when the veositv
Is the same, whatever be the position of the
tube, that is, whether the flowing column
move upward or downward. obliquely or
horizontally. Ia the short arm of siphon,
the column is ascending. Place a choke
valve at the summit. and the impetus of the
rising column will drive water into an air.
vessel then, precisely as The same thing is
done BY the falling column in a common
ram.
In this form, the siphon ram has long
been known. Il operates however, a, a
disadvantage go great az to render il of
no practical utility. This will be under.
stood, ii we observe that the column in the
long arm s not arrested by the choke valve.
but advances ill its momentum is expended,
As no water follows it. the air will tend to
rush Up The arm, but this may be prevented
by bending The end upward, or immersing
it in water. In sma mac lines the ntmos.
pherlc pressure will soon c ,use the column
toFecoil. and then, as the choke.valve falls,
'sthe two columns may peet in opposite d.
nclions paralyzing for a mo ne nj, The uction
3fthe machine. The disalva ntaee IS area.