Sunbury American and Shamokin journal. [volume] (Sunbury, Northumberland Co., Pa.) 1840-1848, 1840-10-31
FROM THE AMERICAN SENTINEL.
Compressed Air as a Motive
Power.
(From our Paris Crrespondtni)

from our rams CUreSponueu.l
Several distinguished engineers and other scien-
tfc men attended on Saturday to witness series
Of experiments on compressed air. at the late esta-
blishment of VI. Perrier & Co. at Chaillot. The
inventor Of the various new and ingenious modes
Of applying this power, NJ. Andsaud, gentleman
well known in the scientific and literary world be-
gan exhibiting a small carriage, which was set in
motion by compressed air on a small railway laid
down for the purpose Of this carriage, was moved
up and down several times at the rate Of sbout %
miles an hour. The air. compressed only to about
25 atmospheres, which Is little more than one third
of the power 10 which II can be compressed without
danger Of explosion, is contained in proof cylcu.
der or reservoir, which supplies the pistons in The
same way as for a locomotive. NJ. Andrsud states,
that two Of these cylenders are sufficient for the
supply Of locomotive for several miles on rail.
way; and as air can be compressed almost without,
expense wherever there is stream or even wind
mill work the machinery. fresh charged cylenders
can he kept ready at stations ond applied the lo-
como'ive this being the work of only one minute.
The improvement in NJ. Andrhud'. air locomotive,
on ali Others which have been invented, is in the
application Of regulator by which the air Is sup
piled with unfag regularity and certainty, and
which is under the full control Of the engineer, and
in the mode Of dilatng the air by heat, so as TO
cause great economy. In dila,ing air il is
ry for the purposes of locomoon, that /, should be
dons very rapidly, for otherwise the speed cannot,
te kept up. II cannot be dilated in the cylender
ir without great danger of explosion; and
by the ordinary process only the external surface
of the air Immediately exposed, the action of hea,
is ripidly dilaed, the internal molecules, sr being
bad conductor, requiring great timo for dilaiion
NJ. Andraud gets rid Of all this difficulty by passing
the air through very long spiral tube immersed in
boiling lead, and in This way the whole Is dilacd in
the twelfth part Of second, aud a reservoir of the
piston, whereas the same quantity Of cir undated
gives only 2,200. Auoher Of the experiments
with an air cannon. Balls were thrown from i,
which. at dist ,nce OF ESQ yards broke in the roof
Of building and lodged with great force in q wall
although the air was compressed to only 30 a,mos-
p ores. NJ Audraud proposes that batteries in for
Iii,d towns shril be worked BY compressed oir in.
stead Of owde, the expense, where there is power
wind - compress the air. Icing, according to NJ.
Pnucol t, only one 18th of that of powder, and il
C, impressed by steam engine about one 50th. NJ
Andraud imagines that field artillery may bo wo'k
ed in the same manner, the horses in drawing
| the ms to the field, would by the motion of the
wheels, fill all the reservoirs n, cessary for long
battle. The next experiment was on the power Of
compressed air in raising water, ihcr for the sup
! ply Of towns or for the draining of marshes, mines,
&c. BY very small apparatus, a column Of water
was thrown to bright Of rs feet.