AN IMPROVED COMPOSITION OR COMPOSITIONS TO BE APPLIED TO STEAM BOILERS AND OTHER SURFACES FOR PREVENTING THE RADIATION OR TRANS- MISSION OF HEAT
Year: 1874

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane,
in the County of Middlesex, Patent Agent, for the Invention of
'AN IMPROVED COMPOSITION OR COMPOSITIONS TO BE APPLIED TO STEAM
BOILERS AND OTHER SURFACES FOR PREVENTING THE RADIATION OR TRANS-
MISSION OF HEAT."-A communication from abroad by Alexandre
Leydet, of Marseilles, France.
Sealed the 29th December 1874, and dated the 21st July 1874:
PROVISIONAL SPECIFICATION left by the said Alexander Melville
Clark at the Office of the Commissioners of Patents, with his
Petition, on the 21st July 1874.
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County
of Middlesex, Patent Agent, do hereby declare the nature of the said
Invention for "AN IMPROVED COMPOSITION OR COMPOSITIONS TO BE APPLIED TO
STEAM BOLLERS AND OTHER SURFACES FOR PREVENTING THE RADIATION OR TRANS-
MISSION OF HEAT," to be as follows:-
This Invention relates to an improved composition for coating the
surfaces of marine and other steam boilers and pipes to prevent the

page_text: The addition of pounded furnace slag imparts great lightness to the
composition, while it possesses the further advantage of being but a
poor conductor of heat, and its extreme porosity also enables it to mix
intimately with clay or aluminous earths.....
The great superiority of the composition lies in its perfect imper-
meability, which renders it proof against the effects of moisture, rain, or
salt water.
This improved composition may also with some slight modification be
applied to water pipes exposed to the action of frost. In this case, after
having applied the composition before specified, I cover the same with a
solution of gutta percha or india-rubber dissolved either-separately.or
together in ether, benzine; spirits of turpentine, or preferably in sulphuret
of carbon, with "which is incorporated silicate of soda or of potash in-
suitable proportions according to the purpose to which the composition-
is to be applied.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Melville Clark in the Great Seal Patent
: Office on the 20th January 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
:
WHEREAS Her most Excellent. Majesty Queen Victoria, by. Her
Letters Patent, bearing date the Twenty-first day of July, in the year
of our Lord One thousand eight hundred and seventy-four, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Alexander Melville Clark, Her special
licence, that I, the said Alexander Melville Clark, my executors,
administrators, and assigns, or such others as I, the said Alexander
Melville 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 "AN IMPROVED COMPOSITION OR COMPOSITIONS TO BE APPLIED TO
STEAM BOILERS AND OTHER SURFACES FOR PREVENTING THE RADIATION OR TRANS-
MISSION OF HEAT," a communication to me from abroad by Alexandre
Leydet, of Marseilles, France, upon the condition (amongst others) that
I, the said Alexander Melville Clark, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands
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.
1 P
NOW KNOW YE, that I, the said Alexander Melville Clark, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement, that is to say :-
This Invention relates to an improved cement or plastic composition:
for coating the external surfaces of marine and other steam boilers. .

page_text: steam chests, and pipes to prevent the radiation of heat therefrom. This
composition not only keeps down the surrounding temperature, but also
conduces to economy in fuel, while it possesses the further advantage of
preserving the surface from rust on which it is applied.
This composition does not emit any disagreeable odour at the ordinary
boiler temperature, which is an advantage not possessed by any coating
of the kind hitherto employed.
:
The following are the ingredients of the composition with their pro-
portions, although these may be varied according to the more or less
plastic nature of the clay or aluminous carths employed :-
In every 100 lbs. of the composition,—
'
The addition of pulverized furnace slag imparts great lightness to the 2
composition, this substance possessing the further advantage of being
but a poor conductor of heat, while its extreme porisity also enables it
to mix intimately with the clay or aluminous earths.
:
The great superiority of the composition lies in its absolute imper-
meability, which renders it proof against the effects of moisture, rain, or 2
salt water. All those who are connected with steam boilers and engines
are aware of the utility and economy of a good composition suitable of
application on those parts of boilers or other surfaces subjected to the
action of moisture, rain, or salt water, which is not liable to be dissolved
and expose the heated metal surfaces on which it is applied. This is a
ensured by the use of the improved composition of this Invention, which
is perfectly impervious to water, and may with some slight modification
be also applied to water pipes exposed to the action of frost. In this
latter case, after having applied the composition before specified, I cover
the same with a solution of gutta percha or india-rubber dissolved either

page_text: separately or together in ether, benzine, spirits of turpentine, or preferably
in sulphuret of carbon, with which is incorporated silicate of soda or of
potash, or both, in suitable proportions, according to the purpose to
which the composition is to be applied. Thus protected the composition
will remain unchanged for an indefinite time under the influence of
moisture.
Having described the nature of the Invention, and the manner of
performing the same, I declare that what I claim as the Invention to be
protected by the herein-before in part recited Letters Patent is, the
improved cement or composition consisting of the several ingredients
herein mentioned intimately mixed together in suitable proportions ;
also rendering the said composition proof against the effects of wet or
moisture, all substantially as and for the purposes specified.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Twentieth day of January,
in the year of our Lord One thousand eight hundred and seventy-
five
Witness,
HY. SWALES,
53, Chancery Lane,
London.
A. M. CLARK. (L.S.)