Massachusetts spy and Worcester advertiser. [volume] ([Worcester, Mass.]) 1823-1825, 1823-10-01
FOR THE MASSACHUSETTS spy.

upon the improvements made by Mr.. Perkins
IN the Steam Engine, endeavored to account
| for the result of his experiments, upon princl-
pies which were well understood many wears
ago, and which have regulated the construc-
ton of great proportion, if not all, of the
steam Engines now in use. The imperfect
description which has been given of his i'm
proVements may not enable us exactly to COM
| prehend their character, and the particular
| mode by which the operations of the eneine
are performed; but the few lights we have
had on the subject have induced me TO believe
that those Improvements consisted merely in
varying the relative proportions of the ma
| chine, so as to increase the temperature of the
steam. by restricting the influence of the heat
to comparatively small quantity of water
| considered the engine of Mr.. Perkins the
same in principle as the high-pressure Engines
of Watt, or Wolff, or Evans; the only ma.
terial difference between them being in the
| difference Of the intensity of heat comn,uni-
| Gated to the water, and that the ADVANTAGE
which this difference gives to the one over the
| others, is obtained by concentrating the heat.
which is the active principle in ali steam en-
gines.
In consequence of the haste in which those
remarks were prepared, one topic was passed
| over, which requires brief notice. 1t is stat
ed IN the article from DIR. Brewster's Journal
that " Mr.. Perkins now entirely dspenses with
the use of the condenser, and works the en-
CINE against the atmosphere alone" Taken
IN connection with the context, the obvious
meaning is that Mr.. Perkins has discovered a
method by which he condenses the steam.
without the aid of cold water, the means
usually employed, so that it may again be re-
turned into the boiler without obstructing the
operations of the engine. 1t is also indirectly.
II not directly stated, that the steam is con-
densed by extracting from it portion of its
heat, which is first returned into the genera
tor, whereby the force of the steam which
drives the piston is increased, while the force
OF that which has acted is diminished or de-
stroyed. II MIR. Perkins has actually discover
ed method by which he can readily transfer
the heat from one portion of steam to another.
and, IN that way, change their elastic forces.
it is indeed a most admirable coptrivanco'
and must be considered as the ne plus ultra of
human ingenuity.
Until such discovery, however, has been
mere clearly demonstrated, must lie permit
| ted to account for the effect produced. upon a
different hypothesis. 1t will be admitted that
the steam, which has once acted, must part
with portion of its heat, before it can be
condensed sufficiently to be returned into the
boiler. This heat, maintain, is entirely Lost,
and not particle Of it finds its way back:
and this loss must be supplied by the combus-
ton OF fuel Now if the water be not sup
piled with heat, by such means, faster than
1t will escape from the steam, which has act
ed, without the aid of the condenser. surely
the condenser can be of no use because. by
extracting the heat at one end faster than it
IS supplied at the other, will diminish the
power OF the engine as effectually as the
counter resistance of the steam to be returned.
But if, on the other hand, the heat is supplied
faster than it will escape of its own accord,
then the application of cold water to aid its
escape, may be useful. For example, steam
at the temperature of 1890 will produce a
pressure CT forty pounds to every square inch;
but if, after it has driven the piston, it should
lose nine degrees of heat, its elastic force will
be diminished ten pounds 10 the square inch.
so that, its counter resistance being but thirty
pounds, it may be returned into the boiler.
/ And if, in this case, the supply of heat be no
greater than the loss, the power of the engine
would not be increased by depriving the re-
turning steam of greater portion of its heat.
Nevertheless, it is manifest, that if the steam
to be returned, should be reduced in its tenn
perature, to 212o the power of the engine
would be forty pounds instead of ten pounds
to the square inch. In that case, however,
as there is less heat returned into the boiler
than in the other case, there must be a greater
quantity supplied, otherwise the force of the
next stroke will be diminished.
If this reasoning be correct, the experiments
of Mr. Perkins may prove that the heat will
escape with sufficient rapidity, without the
use OF cold water, to admit of the steam being
returned into the boiler; and that, at the
same time, there will be surplus of power for
useful purposes; but they are, by no means,
conclusive evidence of the application of any
new principle, either in natural philosophy,
or the mechanic arts.
If Mr.. Perkins is enabled to dispense with
the use of the condenser, it is because he has
carried the high-pressure principle farther than
has before been done. The advantages re-
sultlng from the application Of an extreme in.
tensity of heat TO the boiler, or from con-
centration of its influence, must be apparent.
when the principles which [ have ATTEMPTED
to explain are understood. The effects are
such that the steam, which has once perform.
ed its office, may be returned into the boiler,
with the loss of but a comparatively small
portion of IFS heat; and yet there will more
power remain, after overcoming the counter
resistance of this steam, than is found in what
are called low pressure engines, with the use
OF condenser, or where all the heat is ex
tracted, which gives to the water its elastic
force.
10 demonstrate this proposition more fully,
will once more avail myself of the expert
ments of Mr.. Woolf. 1t has already been
stated, that il steam be raised to the tempera-
ture of 1890. its power will be sufficient to
overcome the power of steam at 273o and
still retain surplus power of ten pounds to
the square inch. Here then thereis a loss Of
but 80 of heat, which is to be supplied by the
combustion of fuel, while the useful power of