A NEW OR IMPROVED SCREEN FOR INTERCEPTING OR STOPPING THE RADIANT HEAT ARISING OR PROCEEDING FROM THE BOILERS OR CYLINDERS OF STEAM ENGINES
Year: 1836

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS JOHN
FULLER, of the Commercial Road, Limehouse, in the County of Middlesex,
Civil Engineer, send greeting.
WHEREAS His present Majesty King William the Fourth, by His Letters
Patent under the Great Seal of the United Kingdom of Great Britain and
Ireland, bearing date at Westminster, the Ninth day of August now last
past, did give and grant unto the me, said Thomas John Fuller, His especial
licence, full power, sole privilege and authority, that I, the said Thomas
John Fuller, my executors, administrators, and assigns, or such others as
I, the said Thomas John Fuller, my executors, administrators, or assigns,
should at any time agree with, and no others, from time to time and at
all times thereafter 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, my Invention of "A NEW OR IMPROVED
SCREEN FOR INTERCEPTING OR STOPPING THE RADIANT HEAT ARISING OR PROCEEDING
FROM THE BOILERS OR CYLINDERS OF STEAM ENGINES;" in which said Letters
Patent there is contained a proviso obliging me, the said Thomas John
Fuller, by an instrument in writing under my hand and seal, particularly to
describe and ascertain the nature of my said Invention, and in what manner
the same is to be performed, and to 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 recited Letters Patent, as in and by the
same, reference being thereunto had, will more fully appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Thomas John Fuller, do hereby declare that the nature of my said Inven-
tion, and the manner in which the same is to be performed, are fully described
and ascertained by the following description thereof, that is to say:-
The nature of my Invention consists in stopping or intercepting the radiant
heat which may be emitted from fuel in a state of combustion, or from
any hot surface or surfaces, by the interposition of a thin stream of cold water
between the said fuel or hot surface or surfaces and such. objects as are
intended to be screened or defended from the influence of such radiant heat,
as aforesaid. The apparatus necessary for effecting such interposition I deno-
minate my hydraulic screen, and I construct the same in the following
manner, that is to say, I make use of metal plates and tubes of brass, copper,
or iron, but in most cases I employ iron plates and tubes as being strongest
and cheapest; with such plates I construct a vessel of any required shape and
dimensions, as, for instance, should the radiating surface from whence the
heat may proceed be such as to require a screen four feet square, I take two
plates of iron, each four feet square, and of about one tenth of an inch in thick-
ness; and between these plates I place a square frame of iron, the four sides
of which are each four feet long, corresponding with the size of the said plates;
each side of the said frame is about one inch in width, and about one quarter
of an inch in thickness; and I cause the said two plates and the said frame so
placed between them to be rivetted together so as to make a water-tight
junction between the said frame and plates all round the margin of the said
plates, thus leaving room between the internal surfaces of the said two plates
for a stream of cold water to be introduced between them, of the same
thickness as that of the herein-before mentioned frame of iron, namely, about
one quarter of an inch. Into the cavity between the said plates I introduce
cold water by means of a tube or pipe (which I call the supply pipe), one end
of which is inserted in a hole through one of the lower corners of one of the
said plates (supposing the plane of the said plates to be in a vertical position),
the other end of the said pipe being made to communicate with a pump
or cistern capable of furnishing a constant flow of cold water through the said
pipe and between the said plates. Into the upper and opposite corner or
angle of the same plate into which the said supply pipe is introduced I
introduce the end of another pipe (which I call the discharge pipe) through
which the water is allowed to pass off and run to waste.
The other end of the
said discharge pipe may be placed in any situation most convenient for getting
rid of the waste water escaping from it. From the description just given of
the construction of my hydraulic screen it will be clearly understood that

page_text: whilst one side of the said screen is opposed to the fire or surface from which
the heat radiates, and at any convenient distance therefrom, the side so exposed
will, by its conducting power, transmit the said heat to the water which is in
contact with it, and that the heat being thus absorbed by the continued
stream of cold water which is made to flow between the said plates, nearly
the whole of the heat will thereby be intercepted and carried off with the
water through the said discharge pipe. In cases where the radiating surfaces
requiring the use of a screen are very large I combine a number of plates by
rivetting them together in the manner commonly employed in the construction
of boilers for steam engines, so as to make the two sides of any one screen of
the required dimensions, or I employ a number of such screens placed edge to
edge so as to fill up the space required. In making use of my hydraulic
screen in steam boats or steam ships to intercept and carry off the radiant heat
proceeding from the front of the boilers employed therein I make an opening
through the lower part of the said screen, opposite to each of the fire doors and
ashpits of the said boilers, so as to allow of sufficient room to open the said
doors, supply fuel to the fires, to rake or clear the fire bars, remove the ashes,
and allow the air to have free access to the fires. In cases where the dimen-
sions of the screen are large the iron plates composing the two sides thereof
require to be held at the proper distance from each other in order to prevent
them from bulging out or receding from each other by the statical pressure of
the water between them. To this end I introduce between the said plates
round collars or rings at the distance of about two feet from each other, and of
a thickness equal to that of the space to be occupied by the water, and rivet
the two sides of the screen together through the central opening in each ring.
The following experiments were made with one of my hydraulic screens,
which was twelve inches square and constructed as herein-before described.
In these experiments I employed cold water of the temperature of forty-eight
degrees Fahrenheit, and causing the same to be passed through the said screen
at the rate of one pint per minute, whilst one side of the said screen was
exposed to radiant heat, which raised the thermometer to three hundred and
seventy degrees; the other side of the said screen remained quite cool to the
touch, but the water which had passed through the said screen and flowed
from the discharge pipe was found to be of the temperature of ninety-three
degrees. I then exposed the said screen to a radiant heat of two hundred and
twelve degrees, and using cold water at the same temperature as in the pre-
ceding experiment, and passing it through the said screen at the rate of half a
pint per minute, I found that the water again flowed from the discharge pipe
at the temperature of ninety-three degrees. From these experiments it is
clear that nearly the whole of the radiant heat was absorbed and carried off by

page_text: the water, and that they afford sufficient data for the quantity of water
required for one of my hydraulic screens of any dimensions, namely, that
if water of the ordinary temperature of river or sea water be passed through
one of the aforesaid bydraulic screens at the rate of about one pint per minute
for every superficial foot in the area of one side of the said screen it will be
found sufficient for the purpose. But in the application of the said hydraulic
screens on board steamboats or vessels, in front and around the sides of the
steam-engine boilers for the purpose of carrying off the extreme heat to which
the steam-engine tenders and workmen are exposed in the engine rooms, and
to defend the timbers and cargoes of such boats or vessels from the injurious
effects produced by constant exposure to the radiant heat of the said boilers, I
believe that the quantity of cold water, at the rate herein-before mentioned,
will be found rather superabundant than not enough. It will, however, in all
cases be better to be on the safe side; I would therefore recommend the
employment of a force pump of such power as would render it capable of sup-
plying cold water to the said screen or screens at the rate and to the extent
herein-before mentioned. Although I have herein-before described the manner
of making an hydraulic screen having its sides flat only, and with a space of
about one quarter of an inch between them, through which the water is to pass,
I must further state, that in applying my hydraulic screen to the curved shape
of the side of a boiler, such as are commonly found on board steam vessels, I
bend the two sides of my said screen into a corresponding shape, so as that
the said screen may be placed in the cavity or space between the side of the
said boiler and the side of the said steam vessel. And I also state that my
only motive for making use of so thin a stream or stratum of cold water
between the two sides of my said screen, as herein-before mentioned, (for any
greater thickness would answer equally well) is to avoid loading the said
screen or screens with unnecessary weight. As the mode of fixing and
supporting my said hydraulic screens in any required positions by iron stays,
brackets, holdfasts, &c., suited to local circumstances is so obvious I need not
particularly describe the same.
And, lastly, I declare that my Invention consists in making a stream or
current of water to pass through a vessel or vessels, such as are herein-before
described, when the same is or are employed for the purpose also herein-before
mentioned.
In witness whereof, I, the said Thomas John Fuller, have hereunto set
my hand and seal, this Fourth day of February, in the year of our
Lord One thousand eight hundred and thirty-seven.
THOS JOHN (L.s.) FULLER.

page_text: AND BE IT REMEMBERED, that on the same Fourth day of February,
in the year above mentioned, the aforesaid Thomas John Fuller came before
our Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained, in form above written.
And also the Specification aforesaid was stamped according to the tenor of
the Statute in that case made and provided.