Im- PROVEMENTS IN APPARATUS FOR GENERATING & APPLYING STEAM AS A MOTIVE POWER
Year: 1862

page_text: LETTERS PATENT to William Clark, of 53, Chancery Lane, in the County
of Middlesex, Engineer and Patent Agent, for the Invention of "Im-
PROVEMENTS IN APPARATUS FOR GENERATING & APPLYING STEAM AS A MOTIVE
POWER, A communication from abroad by Mr. Louis Arnier, of 29,
Doulout Sit Ntautin Davis in the W
PROVISIONAL SPECIFICATION left by the said William Clark at the
Office of the Commissioners of Patents, with his Petition, on the
10th January 1862.
I, WILLIAM CLARK, of 53, Chancery Lane, in the County of Middlesex,
Engineer and Patent Agent, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN APPARATUS POR GENERATING & APPLYING STEAM AS A
MOTIVE POWER," to be as follows:-
This Invention relates to a combination of parts, four in number, ofimproved
form and arrangement, forming one complete apparatus for obtaining and
applying motive power, producing considerable economy in fuel as compared
with that required in other apparatus. The motor in this case is steam as
in ordinary, and the economy is effected in the method of producing and
distributing it, each of the parts comprising this apparatus contributes its
quota of economical effect.
1st. The boiler. This is similar to ordinary boilers, except in the addition
of a row of heating tubes placed in the arch of the furnace, and of a super-
heating apparatus forming a small steam chest herein-after described. These
heating tubes communicate with the boiler at each end, and are filled with
water when the boiler is fully supplied, they communicate at the back with
Price 8d1

page_text: a chamber at the base of the furnace, forming part of the boiler, & in front
they communicate with the water below the water level. In this manner the
tubes are inclined from back to front so that the steam forming therein may
escape freely. The row of tubes also has the effect of dividing the water in
the boiler into thin layers, and thereby considerably augmenting the heating
surface. The arrangement of the heating surfaces centred under the top of
the furnace is infinitely superior to other arrangements as they are exposed to
the full heat of the furnace, and absorb all the caloric evolved. By this
arrangement the whole volume of the boiler and steam chest maybe diminished,
at same time increasing the supply of the latter, as it requires much less water
to supply the lower row of heat deflecting tubes, consequently diminishing the
bulk of the apparatus to au extent equal to the space usually occupied by the
steam chest, which now occupies the place hitherto taken up by the upper rows
of tubes in ordinary tubular arrangements, which are in this dispensed with.
2ndly. The cylinders.-The cylinders are of single action, three in number,
and connected together in the same plane having a three-throw crank shaft,
and working in such manner that when one piston is acted on by the steam in-
troduced into one of the three cylinders, the two other pistons are in their turns
either both acted on by the atmosphere, or one by the atmosphere and the other
bythe expansion of the steam, previously introduced,according to the respective
positions of the cranks on the horizontal shaft. In this manner the power is
obtained with a minimum quantity of steam, and limited to that necessary
for obtaining a vacuum in such manner that the greater part of the motive
power is produced by atmospheric pressure. Thus a considerable quantity
of the steam required in other machines being replaced by atmospheric
pressure a very small amount of steam is sufficient for obtaining a vacuum,
the economy being thus certain and considerable.
3rdly. The reheater.-The reheater affords the advantage of feeding the
boiler with water at a temperature of about 185 degrees Fahrenheit instead of
104° as in ordinary condensing apparatus. This apparatus consists of a channel
placed at the outlet of the cylinders through which the exhaust steam passes
to the condenser. In this channel are a number of small tubes into which the
feed pump forces the water from the trough of the condenser (ata temperature
of about 104 degrees as in ordinary), the steam enveloping these tubes in
its passage to the condenser imparts its heat to the water they contain, and
heats it to a temperature of about 185 degrees Fahrenheit.
4thly. The superheater.-This which forms the fourth and last part of these
improvementspresentsinits turntheimmense advantage of supplying the steain
to the cylinders at a much higher temperature than that it acquires in the boiler.

page_text: It is composed of a cylinder of sheet iron placed vertically at the entrance of
the chimney, serving as a kind of steam chest in the boiler, it is furnished
with a number of tubes for receiving the gases on their way to the chimney,
(after performing their part in the boiler) thence to escape into the atmos-
phere. In this manner it will be easily understood that the steam which is
in contact with said tubes will be raised to the same temperature as the gases
which traverse them, and that it will arrive in the working cylinders with a
greater power of expansion than that it possessed in the boiler. The differ-
ence of expansion of the steam in the boiler and that it attains in the cylinders
furnishes the amount of economy obtained in this part of the apparatus.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Clark in the Great Seal Patent Office on the 10th
July 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
CLARK, of 53, Chancery Lane, in the County of Middlesex, Engineer and
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of January, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-fifth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said William Clark, Her special licence, that I, the said William Clark,
my executors, administrators, and assigns, or such others as I, the said
William Clark, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN APPARATUS FOR GENERATING AND APPLYING STEAM AS A MOTIVE POWER," a com-
munication from abroad by Mr. Louis Arnier, of 29, Boulevart St. Martin,
Paris, in the Empire of France, Mechanician, upon the condition (amongst
others) that I, the said William Clark, my executors or administrators, by an
instrument in writing under my, or their; or one of their hauds and seals,
should particularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.

page_text: NOW KNOW YE, that I, the said William Clark, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Sheets of Drawings hereunto
annexed, and to the letters and figures marked thereon (that is to say):-
This Invention relates to a combination of parts, four in number, of
improved form and arrangement, forming one complete apparatus, for
obtaining and applying motive power, producing considerable economy in fuel
as compared with that required in other apparatus. The motor in this case
is steam, as in ordinary, and the economy is effected in the method of producing
and distributing it. Each of the parts composing this apparatus furnishes its
quota of economical effect.
1st. THE BOILER.
This is similar to ordinary boilers, except in the addition of a row of heating
tubes placed in the arch of the furnace, and of a superheating apparatus,
forming a small steam chest, herein-after described. These heating tubes
communicate with the boiler at each end, and are filled with water when the
boiler is fully supplied. They communicate at the back with a chamber at
the base of the furnace, forming part of the boiler, and in front they com-
municate with the boiler below the water level. In this manner the tubes
are inclined from back to front, so that the steam forming therein may escape
freely. This row of tubes also has the effect of dividing the water in the
boilerintothinlayers, and thereby considerably augmentingtheheatingsurface.
This arrangement of the heating surfaces centred under the top of the furnace
is infinitely superior to other arrangements, as they are exposed to the full
heat of the furnace, and absorb all the caloric evolved. By this arrangement
the whole size of the boiler and steam chest may be much diminished, at same
time increasing the supply of the steam, as it requires much less water to
supply the lower row of heat-deflecting tubes, consequently diminishing the
bulk of the apparatus to an extent equal to the space usually occupied by the
steam chest, which now occupies the place hitherto taken up by the upper
row of tubes in ordinary tubular arrangements, which are in this case
dispensed with.
2ndly. THE CYLINDERS.
The cylinders are of single action, three in number, and connected together
in the same plane, having a three-throw crank shaft, and working in such
manner that when one piston is acted on by the steam introduced into one
of the three cylinders, the two other pistons are in their turns either both

page_text: acted on by the atmosphere, or one by the atmosphere and the other in its
descent by the expansion of the steam previously introduced, according to
their respective positions on the horizontal shaft; in this manner the power
is obtained with a minimum quantity of stean, limited to that necessary for
obtaining a vacuum, in such manner that the greater part of the motive
power is produced by atmospheric pressure; thus a considerable quantity of
the steam required in other machines being replaced by atmospheric pressure,
a very small amount of steam is sufficient for obtaining a vacuum, the economy
being thus certain and considerable.
I will now give a mathematically correct comparison of the steam expended
and power obtained by the engines of the "Hermus," one of the finest of the
Messageries Imperiales steamers working with the least amount of steam,
and that of the "Pleiade," a small vessel fitted with the improved engine
according to this Invention. The following calculations, which are given in
French measures, indicate the steam expended per minute for each of the
engines of the above vessels. N.B.-One mètre equals 3.28 feet; one centi-
mètre equals 0.39 of an inch; one millimètre equals 0.039 of an inch.

page_text: The "Hermus" worked at two atmospheres, and the Pleiades at two-
and-a-half, this difference of pressure is equal to the different amount of
steam expended in each engine; but this pressure may be determined
in litres of water, which should be vaporized per cubic mètre of steam,
according to the pressure of the latter. I will now reduce the expenditure
of steam above indicated into litres of water, so as to have the same unit of
comparison.
131600 litres of steam at 2 atmo-
spheres, the weight of a cubic metre
being 1 k. 122, gives,
131600×1 k. 122-147 1. 655 g.
1650 litres of steam at 2 atmo-
spheres, the weight of the cubic metre
being 1 k. 377, gives,
1-650x1 k. 377=2 1. 272 g.
The power obtained by the two amounts of steam is represented by the
following formula :-
Power.
Surface of piston.
Mean pressure. Motion per second.
T = S
✗
P
C
The mean pressure on the piston of both engines was taken in, curves
given by Watts' indicator.
.N.B. One kilogramme equals 2 lbs. 2055 avoidupois.
For the "Hermus."
T=2.1870×1713x168-62938 kilogrammes.
For the Pleiade.
T 0-3068×0-770×0-72=1700 kilogrammes.
Difference against the latter being 47543 or 4304% on 110481 kilogramètres.
Thus, the single-action engine of the Pleiade produces an economy of
upwards of 43% over the double-action engine of the "Hermus."

page_text: The reheater affords the advantage of feeding the boiler with water at a
temperature of about 185 degrees Fahrenheit, instead of 104° Fahrenheit,
as in ordinary condensing apparatus. This apparatus consists of a channel
placed at the outlet of the cylinders, through which the exhaust steam
passes to the condenser. In this channel are a number of small tubes, into
which the feed pump forces the water from the trough of the condenser,
(at a temperature of about 104 degrees Fahrenheit, as in ordinary); the
steam enveloping these tubes in its passage to the condenser imparts its
heat to the water they contain, and reheats it to a temperature of about
185 degrees at least.
Besides the great economy obtained by feeding with water, which only
requires to be heated about 59 degrees in order to become vaporized, instead
of to 140 degrees, as in ordinary condensing apparatus, this improved appa-
ratus also produces an economy in effect not attained in other arrangements.
Thus, the steam in passing to the condenser begins to be condensed by passing
through the tubes, and partially gives up its caloric to the feed water they
contain, it thus results that the condensation requires only half the quantity
of water required for ordinary apparatus, and consequently the air pump
may be but half the usual size, while there is incontestably much less
absorption of power in working the engine.

page_text: DESCRIPTION OF DRAWINGS.
Fig. 1, Sheet 1, represents a side view of the apparatus on the side of the
furnace, partly in section; Fig. 2 represents a longitudinal section through
the smoke passage of the furnace and the superheater. The improved boiler
to be adapted to the steam engine is shown in a separate Sheet of
Drawings. Fig. 3, Sheet 2, is a vertical elevation of the apparatus on the
side of the driving gear; Fig. 4 is a transverse section through the second
steam cylinder and air pump; Fig. 5, Sheet 3 is a longitudinal elevation of
the steam engine complete; Fig. 6, Sheet 4, is a vertical elevation of the
apparatus on the opposite side to that of the driving gear. The horizontal
shaft A, mounted in bearings B, is furnished with cranks at several points of
its length, which are connected to rods C of pistons D in cylinders E. These
cranks are arranged in such manner, one with the other, that the first is at
the extremity of its course, while the two others occupy intermediate positions,
the second on one side, and the third on the opposite side, so as to divide into
three equal parts the revolutions described by the cranks. I would remark
that the cylinders E are single-acting. The steam from the admission pipe a
is introduced into each of the cylinders passing through the valve boxes F,
and then on the ascending motion of valve b on to piston D of cylinder E,
which communicates at the lower part with the atmosphere, the pressure of
which, together with the combination of cranks on the driving shaft, facilitates
the rising movement ef the piston D, which is kept vertical by rods C working
from the first cylinder the feed pumps G, G, and the bilge pump H, and the
air punip
and traversing guides d, d', of the second and third cylinders.
When the piston D is in its lowest position, the slide valve e allows of the
steam passing from cylinder E into the channel R containing the reheater,
whence it passes to the condenser L, through the columns K. The escape
of the steam and the ascension of the piston are further facilitated by the vacuum
effected at the same time in condenser L by means of a jet of cold water,
while the air pump I forces out the mixture through orifices f,f¹, in its cover.
This pump receives motion from shaft A by means of excentrics g, g¹, com-
municating it to cross bars h, h¹, fixed on rods i, i¹, of piston M. The
distributing valve b, and escape slide valve e, are regulated by a single rod
This rod receives motion from cams p,q,
passing through a stuffing box o.
fixed on an intermediate shaft N, which also receives motion from shaft A
by means of wheel gearing o, o'; in this manner after the cam p has raised

page_text: which
the valve b for admitting the steam, the roller r at the end of rod / falls on
the cam from the effect of expansion, and there remains until the moment
that the piston D has arrived at the end of its course; the rod then again
falls, and opens the escape to the condenser, the roller r turns on the axis of
the cams until the piston has completed its ascending movement, after which
the same operation of admission and discharge is repeated, & the movement
communicated to the driving parts of the engine. The intermediate shaft N
is supported in bearings P; it is furnished with a fly wheel S, on which is a
pinion t, gearing with a wheel n, carried by a loose socket turning on the
end of a lever V, in the form of a crank keyed on shaft N, on the same
socket, and on the other side of the lever there is a pinion x,
in
gears
its turn with a rack z formed in a groove made for the purpose in wheel o².
The object of this arrangement is to permit of the machine being started in
a very simple manner, and solely by manual labour. For this purpose the
fly wheels and pinion t, which form one and the same purpose, are mounted
loosely on shaft N, and the fly wheel is turned by hand, so as to cause the
pinion to traverse rack z (the wheel o' being fixed in consequence of its
rotation with o) until it reaches the other extremity of the latter; this action
displaces the cams p and q, and allows of the rod l again rising by means of
hand wheel m, so as to close the slide exit valve e, opening at same time the
inlet valve b, which admits steam to the piston, and produces an inverse
movement of the driving parts of the apparatus.
Fig. 4, Sheet 2 shows in section a number of small tubes j, disposed
regularly in the escape channel R containing the reheater. The advantage
of this arrangement will be readily understood, as it permits of utilizing the
whole of the heat of the waste steam, which raises the temperature of the
feed water to a certain extent before it reaches the boiler. For this purpose
the tubes j, which traverse the channel R longitudinally, open at each end of
the latter in a single tube, which projects the water from the feed pump
into the steam generator.
On reaching the boiler, the feed water after supplying the upper part,
passes through orifices Q made in the bottom of each furnace into tubes S,
which it traverses, and is thereby exposed to the full action of the fire in
furnaces I, by this means I obtain a much larger heating surface, and con-
sequently the water absorbs in'a given time a much greater amount of caloric.
These tubes communicate with. the boiler at each of their ends, and are full
of water when the latter is fully supplied; they communicate at the back with

page_text: a chamber at the bottom of the furnace, forming part of the boiler, while they
communicate in front below the water level of the boiler; by this arrangement
the tubes will be inclined from back to front, in order that the steam forming
therein shall flow out freely. The fuel which is introduced at the door U
is received in each of the furnaces on grating V, and the flame and heated
gases poduced, after having heated the tube S, pass round tubes X, in
order to heat the upper layers of liquid. On reaching smoke box Y they are
separated in passing through tubes z of superheater W, which contains the
steam, the latter is thereby heated to the temperature of the gases, which
thence escape to the chimney and into the atmosphere. The steam passes
from the steam chest into the superheater, which forms a kind of chamber by
means of two bent tubes placed at back of said chamber, whence the super-
heated steam is conducted to cylinder E by pipe a, herein-before mentioned.
The admission aperture of the steam should be placed as high as possible, and
in front of the superheater. A man-hole is placed at the upper part of the
generator, which affords facility for inspecting and cleaning the interior. The
large amount of heating surface, and the utilization of the whole of the caloric,
rapidly and constantly raises the feed water and the steam to a very high tem-
perature, which allows of an economy of fuel to be realized by the application
of this improved system; in this manner the apparatus will also produce
great economy in the amount of steam required, as, in the majority of cases
the cut-off may be regulated at a tenth only of the stroke of the piston D.
I will now give calculations of the result obtained when trying the single-
action engine above described as compared with the double-action engines
of the same power of the steamer "Hermus." The dimensions, and con-
sequently the power of both engines have been calculated on the following
bases & formulas.

page_text: Thus it follows, that for the single-action screw engine, first, the surface
or area of the steam piston is equal to 1 m. 0568 c.; secondly, that the
volume acted on by the piston is 634 litres.
From this it results, that if the steam is allowed to act on the piston during
it whole course the length of the cylinder, the engine being of single action,
would require for one revolution 634 litres, and consequently for 60 revolu-
tions per minute 634 x 60=38040 litres.
However, under these circumstances, it will be evident that the engine
would work at a disadvantage, as too much steam and also of fuel would be
expended in proportion to the power produced; in fact, the steam thus
constantly arriving in the cylinder at a pressure of one atmosphere and a half
above the atmospheric pressure is evidently still capable, after leaving the
cylinder, of being of further service, as it is still at the same pressure, or if
it is conveyed to the condenser it is completely wasted, while at the same time
it might still serve for producing motive power. Thus, supposing that steam
at one atmosphere and a half, when leaving the cylinder, be conveyed into a
second cylinder of double the size, it will act on the piston of this latter
cylinder at an average pressure of 0.75 of an atmosphere, as the pressure of
the steam is in an inverse proportion to the space it occupies; but instead
of producing this result in a cylinder, which would complicate the machine,
I obtain the same result by cutting of the steam during a portion of the
stroke of the piston, and allowing it to expand during the rest of the stroke.
For example, supposing the steam is only admitted into the cylinder during
three-tenths of the stroke of the piston, and that the steam entering is at a
pressure of 1k. 280 g., as shown by Watts' indicator in the single-action
cylinders of the "Pleiade," the vacuum being 0 m. 60, as shown by Bourdon's
mercury guage, during three-tenths of the stroke the pressure will be equal
to 1-0568x1 k. 280 g. 13527 kilogrametres; but one effecting three-tenths
of the stroke when the steam is cut off, the piston will not continue its course
until the steam contained in the cylinder shall have acted on the piston
with an elastic force which diminished more and more, as the volume of
steam is augmented. It is necessary then to ascertain the amount of power
that may be produced by the piston during its stroke from the admission
to the escape of the steam. Supposing for this purpose the length of stroke
of the piston be 0 m. 60, divided into ten equal parts for example, each
distance would represent 0 m. 60÷10=0.06, and the result for the suc-
cessive distances would be :-

page_text: Consequently the mean pressure of the steam throughout the whole
descent of the piston being equal to the total of the successive pressures
divided by their number will be,
8 k. 495 g. 10 = 0 k. 849 g. per square centimetre.
The vacuum will be the same throughout the return stroke of the piston,
being 0 m. 60 g. of the mercury = 0 k. 815 g.; thus the average for one
complete revolution or turn of the screw will be 0 k. 849 g. +0 k. 515 g.÷2
=0 k. 832 g. per square centimètre of the surface of the piston. The sur-
face of the piston being 1 m. 0568 g., and its course per second 1 m. 20, if
I multiply these by the mean pressure 0 k. 832, it will give the work of each
cylinder per second, which is 1 m. 0568×0 k. 832x1 m. 20-10551 kilo-
gramètres, the real power produced on the three cylinders per second being
10551x3=31653 k. or 31653÷225-140 horse-power,nominal. The power
produced by the three pistons being 31653 k. per second will be, theoretically.
in its power equal to 31653÷75-422 horse-power theoretically; but in
consequence of the friction of various kinds which the piston has to overcome
in all parts of the apparatus, and in the horizontal shaft, in practice the real

page_text: amount of power transmitted to the driving shaft is only 60 per cent. of that
produced by engines of above 100 horse-power, which gives 422 × 0.60=253
effective horse-power for the single-action engine.
I will now proceed to show from given dimensions of guaranteed cor-
rectness, what is the power obtained from one of the double-action engines
of the steamer "Herinus," taking the saine bases as those above for ascer-
taining the power of the single-action engine, so as to prove mathematically
the advantages of this improved system. For the "Hermus" it results,
1st, that the surface of the piston 1 m. 0935; 2ndly, the volume acted on
by the piston for a revolution is 785 litres 320; 3rdly, the admission (for
obtaining nominal power is) 0.68 of it course, 0 m. 72; lastly, the length of
the stroke of piston is 0 m. 72. 1 have before stated that I have endeavoured
to obtain the average pressure, the same as for the single-action engine. I
will first find the pressure of the steam, to which must be added that of the
atmosphere (steam in boiler 1 k. 033, in cylinder 0 k. 858). The stroke
being 0 m. 72,dividing it by 10 will give 0 m. 072 for each successive distance,
but as the admission is 0 m. 68 during the stroke of the piston, the 10% of
72 centimètres gives 72×0.68=0 m. 4596, or × of a tenth of its stroke,
which gives for each distance from 1 to 10, as follows :—

page_text: and the course per second 1 m. 728, if these two are multiplied by
the
pressure, the power obtained from the steam and the vacuum per
second will be 1 m. 0935×1 k. 623 x1 m. 728-30667 kilogramètres, &
30667 kilogramètres 225-136 horse-power, nominal. The force acting
on the piston in this engine being 30667 kilogramètres per second, expressed
in the theoretical horse-power 30667 75-408 horse-power, theoretical;
but in consequence of the friction of various kinds, I estimate the utilizable
power at 0.60% as for the improved engine of this Invention, which gives
408×0.60 245 effective horse-power, 8 horse-power less than the single-
action engine, or 3% in favor of the latter.
=
There now only remains, in order to determine the relative economy of the
two engines, to ascertain the consumption of steam in each per minute, which
obtained, when reduced to pints of water, I will give, by means of a geometrical
scale, the exact saving which exists. In the single-action engine, 1 have
heretofore stated that if the same be introduced throughout the course of the
piston, 634 litres of water would be expended, but, as from calculation, the
expansion is r, 1 only introduce of the 634 litres of water, which, increased
==
one-tenth by waste of any kind 209 litre, and as the engine performs
60 revolutions per minute, the expenditure of steam in the same time for
one cylinder is equal to 209 1. 25+ 60=12555 litres, which, multiplied
for the 3 cylinders, gives 12555 x 3=37665 litres of steam expended per
minute. The weight of a cubic mètre of steam at 2 atmospheres has been
stated to be equal to 1 k. 377.
Thus, by multiplying the number of litres of steam expended by the
weight 1 k. 377, the number of litres of water vaporized in the single-action
engine is 37665 litres x 1 k. 377 51 1. 865 of water per minute, and
51 1. 865 x 60=3112 litres per hour.
Having thus the steam expended for the single-action engine, and the cor-
responding number of litres of water, now there only remains to give in the
same manner the two amounts expended in the double-action engines of the
"Hermus." I have stated that the capacity of the cylinder is 787 litres 32),
the admission orifice being 0-68 centimètres, which gives 787.320X068
=535 litres 577 for one admission; but as the engine is of double-action,
this product must be multiplied by 2, which gives 535-377 x 2=1070 litres 754,
adding to this, as for the other engine, for waste of any kind, gives
1070 1. 754+0=1177 1. 829, and this multiplied by the number of revo-
lutions (72) the engine performs in a minute, gives 1177 litres 829 × 72
=>4803 lit. 688 of steam per minute.
As the weight of the cubic mètre of steam at 2 atmospheres has been stated

page_text: as equal to lk. 122,by multiplying the steam by its weight 84803 1.688x1k.
122 95 1. 149 of water per minute, and per hour 95 k. 149 x 60-5708 k.
938 of water to be vaporized.
COMPARISON.
On comparing the two quantities of water to be evaporized in the two
engines, the following proportions will be found,-
5:08 k. 938 g.
3111 k. 900 g. 100 x
54 k. 511 g.
If the value of x be deducted from 100 k., there remains a saving of
100 k. 54 k.-511 g.=45 k. 599 g. per cent. in favor of the single-action
engine, and which has been obtained in the engines of the Pleïade, near
about, as shown in the calculations herein-before furnished.
In witness whereof, I, the said William Clark, have hereunto set my
hand and seal, this Tenth day of July, in the year of our Lord One
thousand eight hundred and sixty-two.
Witness,
JAMES DAISH,
53, Chancery Lane.
W. CLARK. (L.S.)