AN EXPANDING HYDROSTATIC.PISTON TO RESIST THE PRESSURE OF CERTAIN FLUIDS, AND SLIDE EASILY IN AN IMPERFECT CYLINDER
Year: 1821

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
BOWLES SYMES, of Lincoln's Inn, in the County of Middlesex, Esquire, send
greeting.
WHEREAS His most Excellent Majesty King George the Fourth did, by
His Letters Patent under the Great Seal of that part of the United Kingdoin
of Great Britain and Ireland called England, bearing date at Westminster
the Tenth day of November, in the second year of His reign, give and grant
unto me, the said Edward Bowles Symes, my exors, adñiors, and assigns, His
especial licence, full power, sole privilege and authority, that I, the said
Edward Bowles Symes, my exors, adññors, and assigns, during the term, of
years therein mentioned, should and lawfully might make, use, exercise, and
vend, within England, Wales, and the Town of Berwick-upon-Tweed, mỵ
Invention of "AN EXPANDING HYDROSTATIC.PISTON TO RESIST THE PRESSURE OF
CERTAIN FLUIDS, AND SLIDE EASILY IN AN IMPERFECT CYLINDER;" in which said
Letters Patent there is contained a proviso, that if I, the said Edward Bowles
Symes, shall not particularly describe and ascertain the nature of
my said.
Invention, and the manner in which the same is to be performed, by an
instrument in writing under, my hand and seal, and cause the same to be
inrolled in His Majesty's High Court of Chancery within six calendar months
next and immediately after the date of the said Letters Patent, that then the
said. Letters Patent, and all liberties and advantages whatsoever thereby
granted, shall utterly cease, determine, and become void, as in and by the
same, relation being thereunto had, will more fully and at-large appear.
NOW KNOW YE, that in compliance with the aforesaid proviso, I, the said
Edward Bowles Symes do by these Presents make a full disclosure of the
nature and uses of my said Invention, and I illustrate the same by the

page_text: Drawings hereunto annexed, and by the description of those Drawings herein
contained (that is to say) :-
My expanding hydrostatic piston is formed of a hollow box or vessel, having
the sides made of a flexible substance, and having a pipe arising up from the
top, and communicating with the inside of the said box, and I do fill the said
box and pipe with a fluid until the said finid shall stand at such a height in
the pipe that its gravity shall force or swell out the flexible sides of the box
all around against the cylinder, with a power superior to the resistance of the
fluid within the cylinder, upon or against which I require the said piston to
press. And I do further declare, that in cases where I require a pressure
to overcome a greater resistance within the cylinder than could be given ly
the gravity of a proper fluid in a pipe of a convenient height, I do stop the
upper end of the pipe so as to prevent the escape of the fluid contained
in the piston, and then I place a spring or springs upon the top of the piston,
which shall act upon three or more rods or bolts fastened to the bottom, and
sliding through three or more stuffing boxes in, the top, so that the top and
bottom of the piston shall by these springs be forced towards each other with as
much power as is requisite to cause the contained fluid to swell out the flexible
sides of the piston, to the required degree. And I do further declare, that
I sometimes make the top and bottom of my said piston in one piece, the box
part or hollow receptacle for the fluid being a groove all around the outer edge
of that piece, and on the outside of which groove I fasten on my flexible sides,
and thus form the box part of my piston in the shape of a hollow ring.. And I
do further declare, that one of the uses of my expanding hydrostatic piston is
to press upon the surface of ale, beer, wine, spirituous or other liquors in
an upright barrel, made as nearly of a cylindrical figure. in the inside as can
conveniently be done by common coopers' work, and to continue that pressure
while sinking down upon the surface of the said liquor as it shall be drawn off
for use, and thus of preventing the escape of carbonic acid gas or alcoholic
vapour out of the liquor, as well as the access of atmospheric air to the liquor
which it is well known would injure its quality. And I do further declare, that
another of the uses of my said expanding hydrostatic piston is to slide within
the working cylinder of a steam engine, and to accommodate itself to the
imperfections of the boring of the cylinder without occasioning a great increase
of friction in those parts of the cylinder which are a small degree less in
diameter than the other parts. And I do further declare, that these are the
principles of my Invention, and that they are illustrated, and the manner of
carrying them into effect as shewn in the Drawings hereunto annexed, as
exp'ained by the following description.

page_text: Fig. 1, A shews a plan of my expanding hydrostatic piston for the purpose
of pressing on the surface of ale and other liquors; Fig. 1, B, a vertical
section through the axis of the said piston in the direction (f, f.), of the plan.
The same letters refer to the same parts in the plan, as in the section (a, a, a, a,),
the body of the piston having the top and bottom in one piece, which piece
may be made of queen's ware or any other pottery ware, or any metal that
will not be corroded by the peculiar liquor upon which the piston is intended
to be used. The diameter of the body is to be from a quarter to the half of
an inch less than the diameter of the cylindrical barrel in which the piston.
is to slide. (b, b. b, b,) a belt or hoop of leather, or of painted or oiled cloth
sewed together, or of whalebone or horn rivetted together with several small
rivets, which belt or hoop is tied very tightly into the small grooves (c, c, c, c,)
near the top and bottom of the edge, and covering the large groove (d, d,) in
the middle of edge of the piston; (c, e, e, e,) four pairs of studs projecting up
from the body of the piston, with a hole in cach stud, for the purpose of
fastening a framework to keep the piston in a proper direction within tho
barrel; (f) a cross piece supported by four braces (g, 9, 9,) at a suitable
height above the piston for each end of the cross piece to slide in a straight
groove, crected and fixed parallel to the axis of the barrel; two only of the
braces can be seen in the plan, and three in the section. (h, h,) the two
upright pieces, with straight grooves for the ends of the cross piece to slide in;
(i, i, i, i) the upper part of the barrel in which the piston slides; (k, k,) a
tube of tin or other suitable material fixed into a hole in the body of the
piston, and communicating with the groove (d, d); (1, 1) a cup or cistern at
the top of the tube (k, k,) in which cup there is a piece of cork or other light
substance (m) floating upon the fluid, and carrying an upright graduated
stem (n,n,) which passes through a hole in the cover, and shews at all times
the quantity of fluid in the cup. (p, p,) represents the upper part of the ale
or other liquor in the barrel. From this construction of the piston it is
evident that water or other fluid being poured into the cup (1, 1,) will run
down the pipe (k, k,) and fill the groove (d, d,) and constitute a ring of fluid
pressing outwards against the flexible sides of the piston with more or less
force as the fluid in the cup stands at a greater or a less height above the
piston, which height must be increased in proportion to the imperfection of
the cylindric form of the barrel in which the piston is to slide.
Figure 2, A represents a plan of my expanding hydrostatic piston for
situations where there is not sufficient height above the barrel to admit of an
open tube long enough to give the requisite degree of hydrostatic pressure.;
Fig. 2, B, a vertical section of the same through the axis and through one

page_text: of the stuffing boxes; (a, a, a,) the bottom of the piston, made of tinned
copper, pewter, or other metal: or composition of metals that will not be
corroded by the liquor on which the piston is to be used, in. which bottom
are soldered three bolts (b, b,) having nuts screwed on the upper ends;
(c, c, c,) the top of the piston, having a hole in the middle, into which
is soldered a short upright pipe (d, d); (e,) a cap screwed upon a disc of
leather on the end of the pipe (d, d,) to prevent the escape of the
fluid when pressure is given; (f,f,f,) three stuffing boxes soldered.over three
holes in the top of the piston, only the tops of the nuts. of these stuffing boxes
are seen in Fig. 2, A, and a section of one of them shewn in Fig. 2, B, with
one of the bolts of the bottom passing through it; (9, 9, 9.) a three-limbed
spring with forked ends to take under the nuts of the bolts (b, b,) one of
these nuts is omitted in the plan to shew the fork of the spring; (h, h,) the
flexible hoop or sides of the piston put into circular grooves in the top and
bottom, and secured by hammering the metal tight upon the edge of the hoop,
or by rivets passing through both the metal and the leather, oiled cloth, whale-
bone, horn, or other substance of which the hoop.may be made; (i, i, i,) the
fluid filling the cavity of the piston and the pipe. In this form of my piston
any degreee of outward pressure may be given by screwing down the three
nuts of the bolts (b, b;) or by putting on a weaker or a stronger spring.
Fig. 3 shews another mode of fastening a belt of leather, or painted, or
varnished, or oiled cloth upon the body of the piston. (a, a,) a section of the
body of the piston; (b, b, b, b,) a section of the belt turned over and under the
rim of the body of the piston, and held in that situation by a metal hoop.at
top and bottom (c, c, c, c,) strained within the edge of the belt: and pressing
it tight between the rim and the metal hoop; (d,) a wing, three or more of
which are to be attached to the metal hoop (c), to allow of its being screwed
to the body of the piston, as shewn at (e), to prevent the strain of the belt
from loosening the hoop.
Fig. 4 represents a section of the piston to be used in a steam engine.
(a, a, a, a,) the body of the piston of cast iron; (b, b,) the flexible sides formed
of very thick, hard, and compact woven twine canvas, the best: of such as is
usually made for hose pipes for the conveyance of water.. This canvas is to
be woven of the same width as the circumference of the piston, and a piece
cut off about three inches longer than the depth or thickness of the piston;
"each end of the cloth is then to be hemmed with a very thick and strong hem,
having a cord in the middle of the hem, the distance of the inside of the
hems from each other to be equal to the depth of the piston. This piece of
'canvas so prepared is then to be wrapped around the circumference of the

page_text: piston with one hem overlapping inwards each edge of the piston, in which
situation the two selvedges are to be sewn together with stout pack-thread, and
an iron hoop (c, c, c, c,) put on at each end outside the canvas, the upper edge
of the top hoop being left as high as the top hem, and the lower edge of
the bottom hoop as low as the bottom hem, as shewn at (c, c, c, c,) will
prevent any strain on the canvas from drawing the hems out of their places
without destroying them. (d, d,) the piston rod, which is perforated through
its length; (e, e,) a pipe communicating with the perforation of the piston
rod and with the receptacle around the piston enclosed by the canvas belt;
(fff) the fluid for distending the flexible sides of the piston. The fluid that
I prefer to use in this last described piston is melted tallow or other grease,
with which I supply a cistern similar to (1, 1, Fig. 1, B,) on the top of the
piston rod, about six or eight feet above the level of the piston, when the engine
is worked with steam not exceeding two pounds and a half of pressure to the
square inch. But fat oils that will not harden may be substituted for tallow
when they can be had the cheapest. The small quantity of grease or oil that
will ooze through good canvas will be useful to lubricate the inside of the
cylinder, and save the necessity of applying it to the outside of the piston.
In cases where good compact canvas cannot be procured, I paint the inside
with white lead and oil, or other paint that will bear the heat, or I put a belt
of oiled or painted cloth on the piston under the canvas, or I fill up the pores
of the canvas with a composition of grease and powdered plumbago.
In witness whereof, I, the said Edward Bowles Symes, have hereunto
set my hand and seal, this Twenty-second day of November, in the
T
AND BE IT REMEMBERED, that on the Twenty-second day of November,
in the year of our Lord 1821, the aforesaid Edward Bowles Symes came
before our said Lord the King in His Chancery, and acknowledged the Speci-
fication 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.