IMPROVEMENTS IN APPARATUS USED IN THE WORKING OF STEAM BOILERS, ALSO IN APPARATUS USED IN CLEANING FLUES
Year: 1848

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
ALLIOTT, of Lenton Works, in the County of Nottingham, Bleacher, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Eighth day of March, One
thousand eight hundred and forty-eight, in the eleventh year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said Alexander
Alliott, my exors, admors, and assigns, Her especial licence, full power, sole
privilege and authority, that I, the said. Alexander Alliott, my exors, admors, and
assigns, or such others as I, the said Alexander Alliott, my exors, admors, or
assigns, should at any time agree with, and no others, from time to time and at all
times during the term of years therein expressed, should and lawfully might
make, use, exercise, and vend, within England, Wales, and the Town of Berwick-
upon-Tweed, and in the Islands of Jersey, Guernsey, Alderney, Sark, and
Man, and in all Her said Majesty's Colonies and Plantations abroad, my
Invention of "IMPROVEMENTS IN APPARATUS USED IN THE WORKING OF STEAM
BOILERS, ALSO IN APPARATUS USED IN CLEANING FLUES;" in which said Letters
Patent is contained a proviso that I, the said Alexander Alliott, shall
cause a particular description of the nature of my said Invention, and in what
manner the same is to be performed, by an instrument in writing under my hand
and seal, to be inrolled in Her said Majesty's High Court of Chancery within
six calendar months next and immediately after the date of the said in part
recited Letters Patent, as in and by the same, reference being thereunto had,
will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Alexander Alliott, do hereby declare that the nature of the said Invention,
and in what manner the same is to be performed, are fully described in and
by the present Specification thereof, reference being had to the Drawings
hereunto annexed, that is to say:-
The spindle b', of this
Firstly, my Invention, in so far as it regards the working of steam boilers,
has for its object the improvement of the various sorts of apparatus now ordi-
narily used for keeping the steam boilers in good working condition, and ascer-
taining that they are so, that is to say, the safety valves, the feed valves, the
steam and water indicators, the dampers, and other contrivances whereby the
pressure of the steam, the height of water in the boiler, and the intensity of
the fire can be regulated and ascertained. In carrying out this object, I make
use of different kinds of apparatus, each of which embodies more or less of
the subject matter of my Invention, and these I shall now proceed to describe.
Figure 1, Sheet I, represents a sectional elevation of an apparatus, which
combines in one a steam safety valve, a vacuum valve, and a safety valve,
which acts when the water in the boiler sinks below some given point.. A is
a steam outlet pipe, which is attached by a flange a, a, to the top of the
boiler H. B is a valve with inward action, which fits a seating a', a', formed,
for it on the inner surface of the mouth of the pipe A.
valve passes upwards through an opening a', in the top of the pipe A, and
terminates a little way above it in a circular plate 6, faced square with the
valve B. Round the spindle in the space between the top of the pipe A and
the plate 6 there is coiled a spring &, which rests on a flat boss a, raised on
the curved back of the pipe A. D is an expanding tube made of vulca
nized india-rubber and metal rings, in the manner shown separately on a
larger scale in Figure 4, Sheet I. I form this tube by encircling an india-
rubber tube with rings of tinned copper, placed at equal distances apart,
drawing a second and thin india-rubber tube over the rings, and fastening it
to the inner tube and then subjecting the whole to the well-known process of
vulcanizing. The office of these rings is to support the tube against internal
pressure, whilst at the same time they do not prevent its expansion lengthways.
E is a circular plate, to which the tube D is attached at bottom, and Y anothe
circular plate, to which it is attached at top. The under plate E rests by an
under projecting part e³, on a corresponding projection 6³, raised on the top
of the plate 6, of the valve spindle, and the upper plate Y is upheld by four
studs Y', which are supported by bearings a³, a³, raised on the back of the
steam pipe A. The tube is fastened to these plates by means of convex rings
d', d³, which take into concave seats y³, es, formed for them on the upper face

page_text: of E and under face of Y. Each of these rings is made in two parts, and
joined by flanges as shewn in Figure 4. The upper plate Y remains always
fixed, but the under plate E is free to move when acted upon in the manner
to be presently described. To preserve the parallelism of the plate E when so
moving, it is provided with a guide rod e', which works through a guide frame
y, fastened to the upper plate Y. A tube or ring e', is laid loosely on the top
of the concave seat & of the plate E, and inside of the tube D, but so as not
in the least to restrain it in its movements. The use of this pipe is to support
the tube D in case of external pressure. F is a hand lever for depressing and
so opening the valve B when required. G is a series of copper pipes, which
communicate with the pipe D through an aperture in the centre of the plate Y,
and reach from that plate, as shewn, to some determined level or line in the
boiler, below which, if the water sinks, it is time for the safety valve B to act.
The first pipe of the series 9', is made of the large dimensions shown in order
that it may contain cold water enough to prevent the intrusion of any warm
water or steam into the tube D. The pipe 9², is also made of larger dimen-
sions, in order that it may, by the amount of surface which it exposes, prevent
the formation of steam. 9³ is a tap for drawing off any air which may find
its way into the series of pipes when the boiler has been at rest. By taking
out this tap too, access may be obtained occasionally for cleansing the pipe G.
g' is another tap, through which the tube D is filled with water. By calculating
the internal diameter of the tubo D, and making due allowance for its weight
and the power requisite to make it expand, the results of any given pressure
may be predicated with considerable exactness, but the easiest way for deter-
mining the size which the safety valve B should bear to the expanding tube D,.
is to cause this tube to be subjected to some ascertained pressure, and then to
calculate from the effects produced the size proper to be given to the valve B.
To elucidate the manner in which this apparatus operates, let it be supposed
that it is desired to work the boiler (H) at some pressure below 8 lbs. on the
square inch, and that when the steam becomes above 8 lbs. on the inch pressure,
the apparatus should act so as to allow the steam to escape, and thus restore
the pressure to its normal or safety point. Let it be further assumed, that the
combined weight of the valve B and of the tube D, with the weight due to the
height of the column of water, is equal to 32 lbs., and the power of the spring b*
to sustain B and D is also equal to 32 lbs., we may then obviously throw out of
calculation the weight of the apparatus altogether. Let us now suppose the
valve B to have ten square inches of working surface, and the plate 'E attached
to the expanding tube D to have sixteen square inches of effective working
surface, and the lower end of the pipe 75 of the series of pipes G to be below

page_text: the level of the water in the boiler, then on sufficient pressure occurring in the
boiler, the water will be forced up the long pipe g³, and as soon as the steam
attains a pressure of eight pounds on the inch, there will be a pressure equal
to eighty pounds on the valve B to keep it in its place, while at the same time,
the pressure on the expanding tube D from the steam in the boiler, will be
only five pounds on the inch, (three pounds on the inch being consumed in
supporting the column of water in the series of pipes G from its level in the
boiler to the highest part of the series, which is here supposed to be six feet
high). It follows, that the pressure from the steam on the expanding appa-
ratus will give eighty pounds to push open the valve B, and thus form a perfect
equipoise. Should, therefore, any increase of pressure occur in the boiler,
(the weights and spring remaining the same,) it will cause the valve B to open
inwards, and thus allow the steam to escape, whereby the pressure will be again
reduced to its normal point. It will be obvious that this apparatus may be
constructed so as to allow the steam to escape at any given pressure, by
suitably proportioning the valve B, the expanding apparatus D, and the
spring 6 to one another. The way in which this apparatus acts as a safety
valve when the surface of water in the boiler sinks below the bottom of the
pipe g³ is as follows:-All the conditions of the boiler and valves being sup-
posed to be the same, as in the case last herein-before supposed (by way of
exemplification), the pressure on the valve B will be eighty pounds to keep it
in its seat. Now, on the water in the boiler falling below the bottom of the
pipe go, the water contained in that pipe will of course run down into the
boiler and its place be supplied by by steam, when, instead of there being five
pounds on the inch pressure in the expanding apparatus, there will be eight
pounds, which will give one hundred and twenty-eight pounds of pressure
exerting itself to open the valve B, against eighty pounds exerted to support it
in its place, a difference much more than sufficient to exclude all chance of
danger. It will be found on calculation that at any lower pressure of steam
than has been just supposed a proportionally similar effect will be produced
whenever the level of water in the boiler falls below the bottom of the pipe g³,
and will thus render it impossible to get any pressure of steam in the boiler
until there is water enough in it to make such pressure perfectly safe. In case
of a vacaum or partial vacuum occurring in the boiler, the valve B then acts
so as to remedy it, for as the top plate 6 of the valve B presses only against
the plate E of the expanding apparatus D, it follows that any external
pressure sufficient to overcome the force of the spring 6 will cause the valve B
to open, and thus prevent mischief; the protecting tube preventing any
collapse of the expanding tube D. Instead of the valve B opening inwards

page_text: as before described, it might be made to open outwards by reversing the action
of the expanding tube D, and altering the arrangement of the different parts
accordingly, but in this case it will not act as a vacuum valve.
Figure 2, Sheet 1, is a sectional clevation of a modification of the apparatus
which has been just described, whereby it is adapted to regulate the supply of
water to boilers. K is a pipe leading from the feed pump into a valve box K',
which has two valves seatings and formed on its inner surface, and is
bolted to the top of the boiler H. A is an outlet or delivery pipe; W is a
.cistern, of strength sufficient to withstand the working pressure of the boiler,
and w' is a pipe by which the cistern is connected with the boiler H, the
spindle passing through an orifice in the top of the pipe A, and extending
downwards to a level or line in the boiler, below which it is desirable that the
water should not descend. On this pipe w' are fixed two valves w³, w³, which
fit the valve seatings *, *. From the top of the cistern there rises a spindle b',
which passes through a cross bearing or guide w, and terminates at top in a
circular plate 6'; and in the space between the cross bearings w' and the top
plate be there is coiled round the spindle as before a spring 64. Above the
plate & there is an expanding tube of vulcanized caoutchouc and a series of
tubes leading from it to the boiler all through, as shewn; the tube g³ is fixed
into the top of the boiler. The expanding tube D and cistern W, are here
kept wide apart for the sake of keeping the expanding tube perfectly cool.
The mode in which the apparatus, as thus modified, works, is as follows :--Sup-
posing the weight of the expanding tube D, and its column of water, with the
weight of the cistern W and its other moveable parts, to be balanced or
sustained by the spring 6+, and that the valve we has three square inches of
working surface, and that the effective working surface of the expanding
tube D is two.square inches, then it will follow that the pressure of steam in
the boiler being eight pounds on the square inch, will give twenty-four pounds
on the valve w³ to lift it from its seating. Now, eight pounds on the square
inch on the expanding tube D will give sixteen pounds to hold the valve w³ in
its place (the pipe 9 being, as before stated, fixed to the top of the boiler, and
only acted upon by the steam), and as, there will be now eight pounds more.
upward pressure than downward, it follows that the valve w³ will be lifted
and the valve w³ closed by the same operation, whereby the water coming
from the feed pump through the pipe K. must of necessity pass into the boiler.
Again, on the water rising in the boiler to the height of the bottom of the
pipe w', this pipe and the cistern W will become filled with water; and as this
cistern is supposed to hold fifteen pounds of water, it follows also that the
pressure remaining the same, there will be twenty-four pounds of pressure to

page_text: lift the valve w² from its seating, while as before there will be sixteen pounds
of pressure from the expanding apparatus D, and also fifteen pounds of water
in the cistern, making together thirty-one pounds exerting themselves to shut
the valve. The valve w³ must consequently be closed, and the water escape
through the valve w³ until the cistern W is again filled with steam, when the
same course of action as has been just described will be repeated.
Figure 8, Sheet 1, represents another modification of the apparatus first
herein-before described, whereby in the event of water in the boiler falling
below some desired point an alarum is sounded. A is a pipe which is con-
nected to the valve box K at one end, and to a whistle at the other. W is
a cistern which, as well as the remaining parts of this apparatus, are similar to
those of the apparatus last herein-before described. The operation of this
apparatus is as follows:-The cistern, the valve, and the spring, being adjusted
to one another, so that when the cistern has no water in it it shall leave a
balance of lifting power in favor of the valve w² over and above the depressing
power of the apparatus D, it follows that when steam is admitted to the
cistern W the valve w³ will rise and the whistle act; but on the water
reaching the bottom of the pipe w₁ the cistern will become filled with water,
and the extra weight of this water will overcome the overbalance of the lifting
power on the valve w³, and so cause it to shut.
Figure 8, Sheet 2, is a sectional elevation of another modification of the
apparatus first herein-before described, whereby it is adapted for working
dampers. D is an expanding tube, as before, which is attached by a bottom
plate Y, to a box V, from which a pipe or rather series of pipes G, G, leads
to the boiler, and. terminates at some given level, on the water descending to
which it is desired that the damper should act. m is a spindle which passes
up through and is.secured to the top cover E of the tube D, and is prolonged
upwards as shewn, working at bottom and top in the guide pieces m² and m³;
m' is a rack formed on one side of the spindle; m' is a pinion which takes
into the rack m', and is attached to the end of the axis of a pulley m³; b' is a
spring which is coiled round the spindle between the top guide piece m² and an
under piece m²; made fast to the spindle, and is made strong enough to prevent
the expanding tube D from rising until the required pressure in the boiler is
attained.. N, N, are carrying pulleys; n' is a chain, to one end of which the
damper n² is attached, and to the other a weight n³, which balances the damper;
this chain passes round the pulley m³, and is fastened to it at the point m³.
The mode in which this apparatus works is as follows:-When the steam
has attained sufficient pressure to raise the column of water in the series of
pipes G, G, and to overcome the power of the spring 6' and the friction of the

page_text: moving parts, it will, by the expanding of the tube D, cause the guide rod m
and rack m², to rise, and the action of the rack will turn the pinion m', which
will in its turn move round the pulley m³, which will, through the medium of
the chain n', lower the damper. If, again, the water in the boiler sinks below
the bottom of the pipe G, there will be an immediate increase of pressure on
the tube D, as before explained, which will immediately cause the damper to
close the flue.
Figure 1, Sheet 2, is a sectional elevation of an improved indicator, which
shews at one view the pressure of steam and the height of water in the boiler.
o¹ and o³ are open graduated glass tubes, with cisterns o³ and o, for containing
quicksilver. The method of constructing and graduating such tubes is well
known. P is a copper pipe which reaches from some level or line in the
boiler below which it is desired the water should never sink, and rises to some
convenient height above the cistern o 3, to which it is then brought down and
connected as shewn. In the apparatus now in course of being described the
height of the line 3, above the determined level of water in the boiler is sup-
posed to be three fect, and the height from the line j¹ to the top of the pipe P
two feet. Qis another pipe which reaches from the top of the boiler, and is
connected with the cistern o 4, as shown. It will be observed that the cistern
o 4 is fixed at a lower level than the cistern o3; this is done for the purpose of
shewing on one and the same line the pressure due to the steam and that duc
to the water respectively. The difference of height between the two is regu-
lated by the weight of the column of water to be supported. Thus, if the
desired line or level of water is three feet below the line j¹, and the top of the
pipe Q is one foot above the line j2, then the cistern o 4 requires to be placed
about four inches lower than the cistern o 3. This mode of calculation will
give very nearly the exact distance, but for the sake of greater exactness
it may be desirable to test at some known pressure and height of water in
the boiler the correctness of the arrangement, and if any slight alteration is
required in the height of the cistern o 4, it can then be made by altering the
length of the pipe Q.
The mode in which this apparatus works is as follows:-The line j¹ being
three feet above the determined level of water in the boiler to which the scale
has been arranged, and the top of the pipe P being two feet above the line (¹),
and the pipe P, from p to j', being filled with water, the mercury in the
tube o 1 will rise two inches, corresponding to the pressure of the column of
water in the pipe P; and supposing the top of the pipe Q to be one foot
above the line ³, and the pipe to be filled with water, the mercury in the tube
* 2 will rise one inch, and hence the top of the first inch on the scale of the tube

page_text: o2 is marked zero. Now, on any pressure occurring in the boiler the mercury
will rise in the tube o² in proportion to such pressure, and when the mercury
in the tube o reaches the mark 5 on its scale corresponding to two and a half
pounds on the inch pressure in the boiler, both scales will read correctly; the
first two and a half pounds pressure not acting in the tube o' in consequence
of its being consumed in supporting the column of water rising in the pipe
from the determined level of water in the boiler to the top of the pipe P.
So long, therefore, as the level of water in the boiler remains the same, any
further amount of pressure will be correctly shewn on one line in both tubes,
but if the water rises one inch in the boiler above the determined line, then
the mercury in the tube o¹ will rise one twelfth of an inch above the mercury
in the tube o³, and so on in proportion, shewing a difference above or below
as the water rises or falls, thus exhibiting at one view the exact level of water,
and the exact amount of pressure of steam in the boiler. Again, if the
water sinks below the bottom of the pipe P, and thus danger may be appre-
hended to the boiler, the mercury in the tube o' will immediately rise five inches
above the line of mercury in the tube o³, and by the great difference draw
attention to the danger.
Figure 2 shews an apparatus in which the double indicator last herein-
before described is connected with an alarum. I have here shewn the tubes
as used with mercury and open; but when it is more convenient the same
effects may be produced by using closed tubes and compressed air. When
closed tubes are used, I prefer those made conical for the purpose of equalizing
the scale, and I employ some colored fluid instead of mercury, and so avoid
the clouding of the glass occasioned by using mercury (for compressing air)
in glass tubes. S is a common striking apparatus consisting of a rack wheels',
a bell and hammers and s³, and a weight st. T is a catch lever which is
jointed to a stud t', and rests in the rack of the wheel st. is a spring to
hold this lever up to its work. r is an expanding tube as before (only that it
is placed and worked horizontally instead of vertically) connected with the
pipe P by the pipe, and has a rod 2 fastened to it, which passes through a
bearing 5. is a spring which rests against the bearing r³, and against the
plate Y of the expanding tube r, and must be of strength sufficient to with-
stand the pressure of the steam on the expanding tube r, until it reaches the
pressure at which it is required that the alarum should act.. r¹ and are
two other expanding tubes as before, the former of which is connected with
the pipe P by the pipe, and the latter is connected to the pipe by the
pipe 2-$.
The guide rods of these expanding tubes are connected together
by a coupling. U is a forked rod which rests at one end in the bearing u

page_text: and is joined to the coupling by a cross rod u³, as shewn separately in the plan
Figure 4, Sheet II. The operation of this apparatus is the same as that of
the last herein-before described, with the addition only that, when either the
pressure of the steam is greater than some determined pressure, or the height
of water in the boiler is below some determined point, the alarum is imme-
diately brought into action. The mode in which the alarum s acts when the
pressure of steam is above the determined amount is as follows:-The pressure
overcoming the power of the spring 7, the expanding tuber moves in the.
direction of the catch lever T, and by its rod pushes that lever T out of
gear with the rack wheel s¹, and sets the striking portion of the apparatus at
liberty to sound the alarum. The mode of action in the other case, namely,
that of the water in the boiler falling below some determined point, is as
follows:-The difference in the pressure on the expanding tubes r¹, r³, causes
them necessarily to take certain determined positions, and the end of the
forked rod U is then adjusted so as not to act on the catch lever T until some
alteration in the proportional pressure of these tubes occurs. As long as the
water continues in the pipe P, no sufficient alteration can occur to put the
lever T out of gear with the catch wheel, but directly the water falls below
the bottom of the pipe P two and a half pounds on the inch pressure are
added to the expanding tuber¹, which causes the forked rod U to press against
the catch lever T, and thereby sets the alarum at liberty to act.
In the 'description which I have thus given of various sorts of apparatus in
which expanding tubes are employed, I have not thought it necessary to specify
either the length or thickness to be given to these tubes as these are conditions.
which must depend on the amount of pressure to be resisted. I may, however,
observe generally that it is desirable that the tubes should be somewhat com-
pressed in fixing so as to allow for the subsequent expansion when they come
into action. Pistons may be used instead of these expanding tubes (although
I do not think with the same advantage) as long as the same arrangements
for obtaining the differential pressure are observed. Various other modifica-
tions may be made in the different sorts of apparatus before described in order
to adapt them to different circumstances; but having demonstrated clearly-
the principle on which each is constructed and exemplified, the manner in
which each may be carried out, the modifications proper in each case will
readily suggest themselves to persons of competent skill and experience.
Secondly, my Invention consists of an improved apparatus for cleansing flues,
a sectional elevation of which is given in Figure 1, and plans in Figures 2 and
3 of Sheet 3 of the annoxed Drawings. D is a rod such as is commonly used
in sweeping chimneys, and which may be made in several lengths, screwing

page_text: into one another; and E is a guide wheel affixed to it at top. A is a circular
case made of caoutchouc, cloth, or some other like elastic and air-tight material,
and a', a¹, are a series of rings of gutta percha, which encircle the case cross-
wise for the purpose of strengthening it, and are made in their cross section of
the tapering form shewn. a², a³, are a number of wire cards (such as are
thrown out of use in cotton factories will answer the purpose very well) which
are fastened to the outside of the case A. 6, 61, are six metal rings attached
to the upper part of the case, from which chains or ropes are carried to the
bridle rings c' and c. 63, 6², are six other metal rings, which are attached to
the under part of the case, from which chains or ropes are in like manner
carried to bridlo rings c³ and c. f1 is a cord or chain, which is carried from
the ring round a pulley d³ mounted on the rod D, and attached at the other
end to the ring c; and G is a flexible air-tight tube of the length of the flue
to be cleansed, which is connected by a coupling a³ to the case A. The mode
in which this apparatus is worked is as follows:-Any air there may be in the
case A being free to escape from it through the tube G, it will offer no obstacle
to the passage of the rod D up to the top or outer end of the flue to be
cleansed, but will collapse alongside of it. When the top or end of the flue
has been thus reached, the case A is expanded by blowing or pumping air
through the tube G till it fits the inside of the flue, after which it is worked up
and down by the cord f¹. Should there be any narrow or crooked part in the
Blue the case can be readily cased so as to adapt itself to it by allowing a little
of the air to escape, and afterwards refilling the case, an operation which may
be repeated as often as necessary.
And having now described the nature of my said Invention, and the manner
in which the same is to be performed, I declare that what I claim as constituting
my said Invention is as follows:-
First, I claim the apparatus first herein-before described, in so far as it
combines in one apparatus a steam safety valve, a vacuum valve, and a valve
which acts as a safety valve when the water falls in the boiler below some
fixed level, and in so far also as regards the combination therein of the
expanding tube D, with other parts which are more or less common and well
known.
Second, I claim the employment of the apparatus first herein-before claimed
for the purposes of a safety valve only (excluding its application as a vacuum
valve), and to the extent in other respects before explained.
Third, I claim the feed valve apparatus herein-before described, in so far as
regards the parts marked D and W.
Fourth, I claim the apparatus before described whereby an alarum is sounded

page_text: in the event of the water in the boiler falling below some fixed level, in so far
also as regards the parts marked D. and W.
Fifth, I claim the apparatus for working dampers before described, in so far
as regards the employment of the descent of a column of water in the manner
therein provided for.
Sixth, I claim the combination of a steam indicator and water indicator in
one apparatus, and in manner before described.
Seventh, I claim the combination of the double indicator last herein-before
claimed with an alarum, as before described.
And, eighth, I claim the improved flue-cleansing apparatus before described
in the peculiar combination of parts of which the same consists.
And finally, I declare in regard to each and every one of the sorts of
apparatus or machines or arrangements herein-before described and claimed,
that I make no claim to any of the parts of any of them, as being in and by
themselves, and individually considered, new, but that I claim them only in so
far as they are employed by me in a new state of combination and to the
extent before explained.
In witness whereof, I, the said Alexander Alliott, have hereunto set my
hand and seal, this Eighth day of September, in the year of our Lord
One thousand eight hundred and forty-eight.
ALEXANDER (L.s.) ALLIOTT.
AND BE IT REMEMBERED, that on the Eighth day of September, in
the year of our Lord 1848, the aforesaid Alexander Alliott came before our
said Lady the Queen in Her Chancery, and acknowledged the Specification
5 aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Enrolled the Eighth day of September, in the year of our Lord One
thousand eight hundred and forty-eight.