AN IMPROVED MODE OF PREVENTING CORROSION IN BOILER TUBES
Year: 1861

page_text: LETTERS PATENT to Arthur Wall, of No. 20, Canton Street, East India
Road, Poplar, in the County of Middlesex, Gentleman, for the Invention
PROVISIONAL SPECIFICATION left by the said Arthur Wall at the Office
of the Commissioners of Patents, with his Petition, on the 19th March
1861.
I. ARTHUR WALL, of No. 20, Canton Street, East India Road Poplar, in
the Cy of Middlesex, Gentleman, do hereby declare the nature of the
Invention for "AN IMPROVED MODE OF PREVENTING CORROSION IN BOILER
TUBES," to be as follows:-
I place in the ends of the boiler tubes, where the flame enters, short move-
able tubes which act as guards or protectors to the boiler tubes, and I cover
these moveable tubes as well as the boiler plates, and the boiler tubes them-
selves, or either of them, and either wholly or in part, with platinum, gold,
silver, copper, nickel, tin, zinc, lead, bismuth, or iron, or with a combination
of any two or more of those metals: or, I use the moveable tubes without the
above-mentioned coating being applied to them or to the boiler tubes.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Arthur Wall in the Great Seal Patent Office on the 19th
September 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ARTHUR
WALL, late of No. 20, Canton Street, East India Road; Poplar, in the County
of Middlesex, but now of No. 12, Canton Street aforesaid, Gentleman, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of March, in the year of our
Lord One thousand eight hundred and sixty-one, in the twenty-fourth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Arthur Wall, Her special-licence-that I, the said Arthur Wall, my
executors, administrators, and assigns, or such others as I, the said Arthur
Wall, 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 MODE OF PREVENTING CORRO.
SION IN BOILER TUBES," upon the condition (amongst others) that 1, the said
Arthur Wall, 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.
NOW KNOW YE, that I, the said Arthur Wall, do hereby declare the nature
of my 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)-
For the purpose of preventing corrosion in boiler tubes I place in the ends
of the boiler tubes, where the flame enters, short moveable tubes which act as
guards or protectors to the boiler tubes, and I cover these moveable tubes, as
well as the boiler plates, and the boiler tubes themselves, or either of them,
and either wholly or in part with platinum, gold, silver, copper, nickel, tin,
zinc, lead, bismuth, or iron, or with a combination of any two or more of those
metals; or, I use the moveable tubes without the above-mentioned coating
being applied to them or the boiler tubes.

page_text: The protecting tubes may be made of any refractory metal, or of an alloy of
any two or more of such metals; they may be made either with or without
flanges or ridges at the end nearest the fire to overlop and protect the boiler
plate and to keep them in their place, but if made without, they require fixing
in their place by means of a ring or otherwise in the same way as boiler tubes
are generally fixed; they may be made by casting, or of sheet metal, or by any
other known process; they need not be more than six inches in length, as it is
within that distance of the mouth of the tubes that corrosion mostly takes place,
but I do not confine myself to that length, as they may be made much longer,
even long enough to cover the whole interior of the boiler tubes.
I apply the metallic coating to them and to the boiler tubes, boiler plate,
&c. by electro-plating, electro-gilding, or any other known and available pro-
cess, but I prefer applying it in the following manner: I take pulverised
asbestos, magnesia, talc, steatite, or other magnesian earth or combination of
magnesian earths, and place it in a pot, pan, or crucible, or any other conve-
nient vessel, and then pour over it muriatic, hydrochloric, sulphuric, or nitric
acid, or a mixture of two or more of such acids (preferring, however, sulphuric
acid), until the mass is saturated, and then either in that state or after having
added a small quantity of water, I place it in an oven or furnace, or in or over
a common fire, or otherwise subject it to a heat sufficient to boil it; and when
the superfluous moisture has evaporated and the mass is nearly dry, I take it.
from the oven, furnace, or fire, and allow it to stand several hours to cool.
When it is cold I add to it the metal or metals I intend applying as a coating,
in combination with an acid, or in the form of an oxide, in the proportion of
from four to eight ounces thereof to a pound of the first-mentioned preparation,
according to the quantity of metal contained in the solution or oxide (observing
first, in the case of solids, to reduce them to a powder). I then stir the mass,
adding to it a sufficient quantity of spirits of wine, naptha, napthaline, or other
spirit, or acetic, pyroligneous, or other vegetable acid, or a spirit and an acid
mixed, to reduce it to the condition of a wash or paint, when it is ready for
use; and I then apply it to the surfaces to be treated by dipping, brushing, or
any other of the ordinary and known modes of applying washes or paints.
For the purpose of protecting the coating of the tubes and boiler plates from
being scratched or scoriated by particles of cinder or unconsumed fuel, I place
across the furnace in front of the boiler plate a close metallic grating, to pre-
vent such particles from being carried into the tubes; this grating may be
covered or coated in the same way as tlie tubes, &c., to preverve it from the
action of the fire and the acids generated therein.

page_text: Having thus described the nature of my said Invention and the manner in
which the saine is to be performed, I declare that the parts thereof I claim as
new are the following:-
First, using the moveable or protecting tubes I have mentioned for the
purpose herein stated.
Second, coating the surfaces thereof and of the boiler tubes themselves and
the boiler plates with metal, either alone or combined with other substances,
in the manner herein described.
Third, using the grating in front of the boiler plate, as before described.
In witness whereof, I, the said Arthur Wall, have hereunto set my
hand and seal, the Eighteenth day of September, in the year of our
Lord One thousand eight hundred and sixty-one.
ARTHUR WALL. (L.S.)
Witness,
THOS. HALE,
Clerk to Grover & Eldred, Solrs.,
8, G. James Street, Bedford Row,
London.