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The engineer's and mechanic's encyclopædia, comprehending practical illustrations of the machinery and processes employed in every description of manufacuture of the British Empire .. (Volume 2) online

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previously filled with air. The pressure of the atmosphere (very nearly fifteen
pounds to the square inch) will then exert itself upon the external sides of the
vessel, which, if too weak to resist such a force, will become necessarily
crushed together. Again : if the vessel be of a cylindrical figure, closed at the
bottom, and its open top fitted with a movable piston (in contact with the
water partially filling the cylinder), the piston will be raised as the steam
becomes generated ; now, if before the piston arrives at the top, the fire be
removed, and cold be applied to the sides of the cylinder, the steam, becoming
thereby condensed, leaves a void which is instantly filled up by the descent of
the piston acted upon by the atmosphere pressing upon its exposed surface
without.

Whatever may be the construction of a steam-engine, every modification of
it derives its power from one or other of these two principles, or from both in
combination.

The two tables given for greater perspicuity in the next page the first being
the result of a series of experiments made by Dr. Dalton, the second supplied by
the Royal Academy of France, in their report upon the comparative degrees of
safety between high and low pressure engines are inserted, as being not only
essential to the working engineer, but interesting to the general inquirer : they
differ in no very material point with other calculations that have been made, and
are quite near enough to be adopted as a standard for guidance in practical
operations.

The origin of this invention became, long ago, a matter of earnest inquiry ;
the conception and contrivance of a machine of such rare importance
becoming points of great interest to the scientific world. Posthumous fame,
though it may be a stirring incentive to the living, is of little consequence to
the dead ; still it is a creditable sentiment to desire to render homage where it
is truly due, and to invest with honour the names of those who, by their illus-
trious acts, really deserve it. But where nations themselves become exalted by
the achievement of an individual, that sentiment is often accompanied by unbe-
coming prejudices, which warp the judgment, and convert the enquirer into a
jealous partisan. Sharp controversies are originated and maintained in an
unbrotherly spirit, and truth, already mystified by the veil of time, becomes
more difficult of attainment than ever by the very efforts of the disputants
themselves.

French writers affirm that to their country belongs the glory of first inven-



STEAM-ENGINES.



691



TABLE

Of the Expansive Force of Steam when contained in a closed Vessel, taken at every
10 of Temperature from 212 Fahrenheit, (the Boiling Point,) up to 320.





Pressure of Steam, or the Force which


Pressure of the Steam against the
Atmosphere, when the Barometer is




it will exert to enter into a vacuous


at 30 Inches, or the Force it will ex-


TEMP.


Space.


ert to escape from the closed Vessel






into the open Air.


Fahr.


Column


Column


Pressure


Column


Column


Pressure




of


of


per


of


of


per




Mercury.


Water.


Square Inch.


Mercury.


Water.


Square Inch




Inches.


Ft. In.


Lbi. Oz.


Inches.


Ft. In.


Lbs. Ox.


212


30.


33 J 11


14 11


The Steam


equal to the


atmosph.


220


35.


39 6


17 1


5.


5 7


2 7


230


41.75


47 2


20 7


11.75


13 4


5 13


240


49.67


56 1


24 4


19.67


22 3


9 10


250


58.21


65 9


28 8


28.21


31 11


13 14


260


67.73


76 6


33 2


37.73


42 8


18 8


270


77.85


87 11


38 1


47.85


54 1


23 7


280


88.75


100 3


43 7


58.75


66 5


28 13


290


100.12


113 1


49


70.12


79 3


34 6


300


111.81


126 4


54 12


81.81


92 6


40 2


310


123.53


139 6


60 8


93.53


105 8


45 14


320


135.


152 6


66 1


105.


116 5


51 7



Elasticity
in
Atmosphere.


Height of Mercury
in
Inches.


Temperature
of
Fahrenheit.


Pressure
per Square Inch, in
Ibs. Avoirdupois.


1


29.92


212.


14.61


||


44.88


234.


21.92


2


59.84


251.6


29.23


3


89.76


275.


43,84


4


119.69


293.4


58.46


5


149.61


309.2


73.07


6


179.53


322.7


81.69


7


209.45


334.4


102.30


8


239.37


343.4


116.92



692



STEAM-ENGINES.



Fig. 1.



tion ; English authorities deny the claim, and insist that it belongs to theirs,
Others, on the contrary, refuse it to both; and, referring to the disclosures made
in the works of scientific men who existed in remote times, pronounce judg-
ment, some in favour of Egypt, and some of Italy ; whilst, in reality, the steam-
engine, growing, as it has done, in gradual formation and perfection, under the
contributions of men of genius living in different countries and at different
periods, may in strictness be regarded rather as the elaboration of an age than
us the sole product of any one master-mind.

The first person we find in the records of antiquity now open to us as an
experimentalist upon steam, is HERO the Elder, the son of a Greek, settled at
Alexandria, who flourished about 130 years before the Christian era. In his
work entitled Spiritalia, he describes, among other ingenious machines, three
modes in which steam might be employed as a mechanical power : to raise
water by its elasticity ; to elevate a weight by its expansive force ; and to pro-
duce a rotatory motion by its reaction on the atmosphere. Toy-like as they
appear, they deserve illustration.

Fig. 1, On the lid of the box, or cistern a,
containing water, Hero placed a globe c,
also partly so filled ; a pipe e rises from the
cistern into the globe. Another pipe i pro-
ceeds from the globe, terminating over a
vase m, and the vase itself communicates
with the cistern by a pipe n. When the
sun-beams fall on the globe, they heat the
water, and raise vapour ; this, by its expan-
sion, forces the water through the syphon i,
which, trickling into the vase m, is again
conducted by the pipe n, placed within it,
into the cistern. When the-sun-beams are
withdrawn, and the surface of the globe

cooled by the surrounding air, the vapour within is condensed, and, by this
means, a void is left in its upper part : the pressure of the atmosphere now
forces the water in the cistern up the pipe e, to replenish it ; and the same
operation of forcing water commences, wnen the sun's rays, falling on the sur-
face of the globe again, heat its contents. Here, almost under any circum-
itances, the effect could have been but trifling; but in the second, Fig. 2, where




Fig. 2.



Fig. 3.





we heat from a lamp or fire is substituted in the place of that proceeding
from the sun, the power would not only be more available, but less hypothetical.
A caldron a has a pipe c, (arising from its lid) shaped at its upper end cup-wise,
for holding the ball or hollow sphere o. A fire being made under the caldron,
the steam rising from the water which it contains flows through the pipe, and
lifts up the ball placed in i to a height proportioned to the force of the steam.



STEAM-ENGINES.



693



Fiy. 3 shows the mode by which a small globe is made to revolve on its axis.
Two pipes, a c, each having its upper extremity bent towards the other, rise
from the cover of the caldron o; one of these, o, acts merely as a uivot. the
other, a, conducts steam, raised in the boiler, into the hollow globe i. This is
suspended between them by having the steam-pipe a inserted into it, and is
kept in its position by the pivot formed at the end of the opposite pipe c. Two
hollow pipes n, also ben.t at right angles at their extremities, are inserted at the
circumference of the globe, and form a communication between the caldron
and the atmosphere. Heat being applied to the bottom of the caldron,
the steam issuing through the vertical pipe a into the globe i thence finds an
exit from the arms n, and, by the reaction of the air, makes the globe revolve
on its axis with great celerity, "as if it were animated from within by a living
spirit."

Here, then, do we find the two properties of steam, expansion and contrac-
tion, recognised and applied almost two thousand years previously to the time
of their being availed of for any efficient purpose. Scientific bauble?, to be
sure, were these contrivances ; but in them we have the undoubted germs of the
vast and extensive power which its present modification permits. Hero, in his
Introduction, professes to have made himself acquainted with the works of his
predecessors and contemporaries, and, admiring their simple ingenuity, and
unwilling that such fine inventions should perish or be overlooked, describes
them, that they may be better and more generally understood. So that these
very properties of steam may have been, and probably were known long prior
to the time in which he flourished.

The next attempt of which history apprises us, to reduce steam to an
agent of power, is described in a work by SOLOMON DE CAUS, an eminent
French mathematician and engineer, published in 1615, entitled, Les Raisons
des Forces mouvantes avec divers Desseins de Fontains. The following descrip-
tion will explain the principle of his device.

The caldron a is furnished with two
pipes, b e, the latter of which reaches
nearly down to the bottom of a. The
pipe b is furnished with a cock d and
funnel c. The vessel being nearly filled
with water, and the cock d shut, fire is
applied, as in Hero's vessel Fig. 2, and
the steam, pressing on the surface of the
water, forces up the lowermost portion
through the tube e to a height propor-
tioned to its temperature. This is, cer-
tainly, another step in advance ; but
without wishing to disparage the inge-
nuity of De Cans, it may be doubted
whether the notion is really his own ;
for in his dedicatory address to the
French king, he invites His Majesty's
especial attention, not so much to effect
produced by this operation of the steam,
as to his happy device of increasing the
sun's influence on his apparatus by the
intervention of the lens a charcoal fire
being far too simple an affair to catch his
regards. He was well aware that the
steam generated from boiling water
became condensed into its pristine state
of water on being cooled, and to "juste-
ment la mesme quantite ;" but the know-
ledge of this fact appears to have
provoked no further speculation in his
mind.




De Causs Engine, 1615.



694 STEAM-ENGINES.

In 1629 BRANCA, an Italian architect and engineer, published a book, in
which he describes a novel application of steam. His illustration is ingenious
and pretty ; for, substituting the human head and face in lieu of the cover of
Hero's caldron (as shown in the cut), he conducts a tube to and beyond the
lips of the figure through which the steam passes, and acts on the vanes of a
wheel that is thus made to revolve on its axis by the impetus of the escaping
steam, and so give motion to other wheels connected therewith. This certainly
conveys the first published idea of employing steam as a prime mover ; but
whilst one writer is disposed to concede to him the merit of a first suggestion,
another, again, regarding his book as containing a collection of machines
invented by others, assumes it to be " an idea of which he is only the mere
illustrator." It is obvious that the force obtained from steam so applied, would
be very slight, even had the notion been carried into practice.

It will have been seen, then, from this hasty narration, that up to this
period, Branca's publication, in 1629, none of the experiments made with
steam had led to a conception of its gigantic capabilities ; nor, subsequent to
that date, until up to the middle of the seventeenth century, have we any further
records of its advances.

We now, however, arrive at a new and memorable epoch in the history of the
engine ; namely, the experiments and disclosures made by the MARQUESS of
WORCESTER, about the middle of the seventeenth century. In 1663 that
nobleman published his extraordinary book, the Century of Inventions,
giving a brief account of one hundred devices of his inventive genius. Amongst
these inventions, (numbered 68,) appears the description of a fire water-work,
which is here transcribed. [Note. The original manuscript of this work,
written in the year 1655, is now preserved in the British Museum.]

" An admirable and most forcible way to drive up water by fire ; not by
drawing or sucking it upwards, for that must be as the philosopher calleth it
intra sphtzram actiwiiatis, which is but at such a distance. But this way hath no
bounder, if the vessel be strong enough ; for I have taken a piece of a whole
cannon, whereof the end was burst, and filled it three quarters full of water,
stopping and screwing up the broken end, as also the touchhole, and making a
constant fire under it ; within twenty-four hours it burst, and made a great
crack : so that, having a way to make my vessels, so that they are strengthened
by the force within them, and the one to fill after the other, I have seen the
water run like a constant fountain-stream, forty feet high : one vessel of water,
rarefied by fire, driveth up forty of cold water, and a man that tends the work,
is but to turn two cocks, that one vessel of water being consumed, another
begins to force and refill with cold water, and so successively, the fire being
tended and kept constant, which the self-same person may likewise abundantly
perform in the interim between the necessity of turning the said cocks."

It may be supposed that the Marquess, with a mind so ardently disposed to
mechanical projects, had made himself acquainted with the attempts of his
predecessors to employ steam as a motive force ; it is plain, however, that he
must have made advances and discoveries upon the subject far beyond those of
other philosophers who had gone before him. He speaks of his contrivance as
a power inherently WITHOUT BOUNDER, and only limitable by the weakness of the
vessels that confine it. Its vastness and docility to human control (of which no
experimenter before his time ever appeared to have considered), were evidently
well appreciated by him, and must have been demonstrated to him by practical
results. This assumption is supported by the manuscript prayer found after his
death among his lordship's papers, entitled by him, " The Lord Marquess of
Worcester's ejaculatory and extemporary Thanksgiving Prayer, when first with
his corporal eyes he did see finished a perfect trial of his water-commanding
engine, delightful and useful to whomsoever hath in recommendation either
knowledge, profit, or pleasure."

Unless the Marquess's veracity is doubted, it is pretty clear, therefore, that an
engine (rude of contrivance it may be,) was actually constructed by him to raise
water by the repellant power of steam. He speaks of having " seen the water
run like a constant fountain-stream;" and of the force produced, and its



STEAM-ENGINES.



695



extent " a stream forty feet high ; one vessel of water rarefied by fire draweth
up forty measures of cold water." " His having a way to make his vessels," so
that they are strengthened by the force within them, and the one to fill after the
other, is not to be regarded as the conjectures of an ardent mind, merely
because the results of his experiments are declared to be consequent upon the
mode of construction ; " so that having a way, I have seen," and so on. Many
attempts have been made to reduce the meaning of this celebrated description
into some appreciable form ; but as it, like the greater part of his other descrip-
tions, is (perhaps purposely) mysterious, designed rather to provoke attraction
than to afford a clear conception of a great mechanical invention, no wonder
such attempts have been mostly unsatisfactory. The "forcing and refilling," and
, the " strengthening of a vessel by the force within," would seem, when taken
in an unrestricted sense, to be manifest absurdities, and no conjecture yet offered
has sufficed to explain away the error which his inexplicit announcement
conveys. An illustration of his possible meaning has been offered by a writer
(Mr. Galloway) on this subject in the following figure and description.
(See Galloway and Hebert's History and Progress of the Steam-engine.)




The Marquess of Worcester's Engine, 1663.

In this figure a represents the boiler, composed of arched iron plates, with
their convex Rides turned inwards; they are fastened at the joinings by bolts
passing through holes in their sides, which also pass through the ends of the
rods i i i, a series of which rods extend from end to end of the boiler, being a
few inches apart. The ends of the boiler are hemispherical, and are fastened
to flanges on the plates hhhh. It will be evident that, each plate being an



696 STEAM-ENGINES.

arch, before the boiler can burst, several, if not. nearly all the rods ii, must
either be pulled asunder or torn from the bolts at the points of junction ; and as
the strength of the rods and bolts may be increased to any extent, without
interrupting the action of the fire, there can be no doubt that a boiler might be
so constructed as to be perfectly safe under any pressure which could be required
for raising water to a given height, because the pressure in such a boiler will
never exceed the weight of a column of water equal in height to the elevation
of the cistern, be represent two vessels, which communicate with the boiler a,
by means of the pipes //, and three .way-cocks m n, and with the reservoir from
which the water is to be drawn by the pipes / /. gg are two tubes, through
which the water is elevated to the cistern ; they reach nearly to the bottom of
the vessels b c, and are open at each end. The pipe /, as well as //communicate
with the vessels be by means of the three way-cocks m n, which, by moving the
handles op, can be so placed, that either the steam from the boiler, or the water
from the reservoir, shall instantly have access to the vessels b c.

Fire having been kindled under the boiler a, in the furnace d, " the man who
tends the work " places the cock n in the position represented in the drawing,
when the water will have free access from the reservoir to the vessel c, which
being filled, the handle p is turned back, so that the cock shall be relatively in
the position shown at m ; the steam then fairly enters through the pipe /, into
the vessel c, and having no other mode of escape presses on the surface of the
water, which it forces up through the pipe g. During this operation, (the
cock m having been placed as shown at n) the vessel b is filling from the
reservoir, through the pipe /; so that the water in the vessel c being consumed,
the man turns the handle o of the cock p, and admits the steam on the surface
of the water in b, shutting off, by the same operation, the communication
between b and the reservoir; the other then begins to repeat the act of filling
the cistern, "and so successively, the fire being tended and kept constant."

This conjectural device may serve to convey an idea of the Marquess's am-
biguously-described invention. No model or drawing of the apparatus actually
proposed by him has been discovered, so that any attempt at explanation must
be left entirely to the imagination, assisted as it now is by the discoveries sub-
sequently made ; beyond the mere announcement conveyed in the 68th item of
his century, the labours of the Marquess upon the power of steam were intrin-
sically valueless, excepting in so far as they may have stimulated succeeding
experimenters. He unquestionably conceived a great design, and declared its
execution, but he left no beacon for their guidance and assistance : he was evi-
dently a man of much knowledge and ingenuity; but the apparent extravagancies
scattered throughout his work, coupled with "the bombast and obscurity of his
expression, must have excited sceptical doubts, and given sanction to the
suspicion then entertained of his capacity to realize his schemes. Several of
them appeared to be in direct opposition to the rules of science then established
and well understood, and his account partook too much of the marvellous, to
win the confidence of his learned contemporaries, or that public encouragement
which he importunately solicited, but failed to obtain. The Century of Inven-
tions was published three years after the formation of the Royal Society, and
during the^time of Mr. Boyle, Dr. Hooke, Dr. Wallis. Sir Christopher Wren,
Sir Isaac Newton, and other persons illustrious for their learning and genius,
so that he had not to complain of the ignorance of the age in which he lived,
whatever might have been its prejudices. It is not surprising, therefore, that
with such pompously announced and unintelligible projects, he should defeat his
own object to obtain public patronage, nor that he should have been considered
the " fantastic mechanic," which Walpole calls him.

Nevertheless, his account of the " fire-water work" must be taken as the first
veritable record of the steam-engine^ as at least a power without bounder, and to
its author be ascribed the honour of suggesting it as such.

In 1683 Sir SAMUEL MORLAND, the son of a Baronet of the same name,
submitted to Louis XIV., of France, a contrivance for raising water by the aid
of steam. No record remains of his apparatus, but as the account given by
him in his manuscript, among the Harleian papers, affords ample evidence of



STEAM-ENGINES. 69T

his knowledge as to the application and force of steam, it is but just to include
it in this sketch. It is written in the French language, and may be thus
translated.

"The principles of the new power of fire, invented by the Chevalier Morland
in the year 1682, and presented to his most Christian Majesty, 1683. Water
being evaporated by the power of fire, the vapour shortly acquires a greater
space (near 2000 times) than the water occupied before ; and were it to be al-
ways confined, would burst a piece of cannon. But being well regulated accord-
ing to the laws of gravity, and reduced by science to measure, to the weights
and balance, then it carries its burdens peaceably, (like good horses,) and thus
becomes of great use to mankind, particularly for the elevation of water, ac-
cording to the following table, which marks the number of pounds which may be
raised 1800 times per hour, by cylinders half full of water, as well as the different
diameters and depths of the said cylinders."

The tables need not be given, but his calculations upon the force of steam are
very correct, and evidently the result of great care.

In 1698, Captain THOMAS SAVERY obtained a patent for a new invention for
raising water and occasioning motion to all sorts of mill-work, by the impellant
force of fire ; and the patent states that the invention will be of great use for
draining of mines, serving towns with water, and for working all sorts of mills.
Previously to the date of this patent, he had erected several machines,, of which
an account is given by him in a book entitled The Miner s Friend, published
in 1702; and in June, 1699, he showed a working model of his engine to the
Royal Society ; and in their Transact Io7is for that year (No. 253, Vol. XXI.)
there appears the following register :

"Mr. Savery, June 14th, 1699, entertained the Royal Society with showing
a small model of his engine for raising- water by the help of fire, which he set
to work before them ; the experiment succeeded according to expectation, and
to their satisfaction."

This is accompanied by a copper-plate figure, with references, by way of de-
scription, from whence it appears that the engine then shown by Captain Savery
was for raising water not only by the expansive force of steam, like the Mar-
quess of Worcester's, but also by ilie condensation of steam, the water being first
raised by the pressure of the atmosphere to a given height from the well into the
engine, and then forced out of the engine up toe remaining height, by the ex-
pansive force of steam, in the same manner as proposed by the Marquess. This
action was performed alternately in two receivers ; so that while the vacuous space
formed in one was drawing up water from the well, the pressure of the steam in
the other was forcing up water into the reservoir ; but both receivers being sup-
plied by one suction-pipe and one forcing-pipe, the engine could be made to
keep a continual stream, or so nearly so, as to suffer very little interruption.

The following figure and description, nearly in Savery 's own words, will illus-



Online LibraryLuke HebertThe engineer's and mechanic's encyclopædia, comprehending practical illustrations of the machinery and processes employed in every description of manufacuture of the British Empire .. (Volume 2) → online text (page 102 of 135)