IMPROVEMENTS IN PREVENTING THE INCRUSTATION OF STEAM BOILERS
Year: 1858

page_text: LETTERS PATENT to Eugéne Coulon, of Croisset, near Rouen, France,
for the Invention of "IMPROVEMENTS IN PREVENTING THE INCRUSTATION OF
STEAM BOILERS."-A communication.
Sealed the 10th September 1858, and dated the 23rd March 1858.
PROVISIONAL SPECIFICATION left by the said Eugéne Coulon at the
Office of the Commissioners of Patents, with his Petition, on the 23rd.
March 1858.
I, EUGENE COULON, of Croisset, near Rouen, France, do hereby declare the
nature of the Invention for "IMPROVEMENTS IN PREVENTING THE INCRUSTATION
OF STEAM BOILERS," to be as follows:-
This Invention has for its object improvements in preventing the incrusta-
tion of steam boilers, and consists in employing for that purpose the plombates
and plombites of potash and soda, the insoluble salts of lead, and chloride of
zinc. A quantity of one or more of these substances is either placed in the
reservoir of water from which the boiler is supplied, or is added from time to
time to the water in the boiler, and I prefer to add to the substance or sub-
stances employed a quantity of sand, clay, red ochre, and muriatic acid.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Eugène Coulon in the Great Seal Patent Office on the 18th
September 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EUGÈNE
COULON, of Croisset, near Rouen, France, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of March, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant. unto me, the
said Eugène Coulon, Her special licence that I, the said Eugène Coulon, my
executors, administrators, and assigns, or such others as I, the said Eugène
Coulon, 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 "IMPROVEMENTS IN PREVENTING
THE INCRUSTATION OF STEAM BOILERS," upon the condition (amongst others)
that I, the said Eugène Coulon, my executors or administrators, by an instru-
ment 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Eugène Coulon, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
This Invention has for its object improvements in preventing the incrustation
of steam boilers, and consists in employing for that purpose the plombates and
plombites of potash and soda, the insoluble salts of lead, and chloride of zinc.
A quantity of one or more of these substances is either placed in the reservoir
of water from which the boiler is supplied, or is added from time to time to
the water in the boiler, and I prefer to add to the substance or substances
employed a quantity of sand, clay, red ochre, and muriatic acid.
And in order that my said Invention may be most fully understood and
readily carried into effect, I will proceed to describe, in the first place, the
method in which I prefer to operate when employing plumbate or plumbite of
potash or soda to prevent incrustation in a boiler fed with fresh water. I

page_text: dissolve the salt employed in water, and by preference I add the solution to the
water in the reservoir from which the boiler is supplied, so that the boiler may
be at all times supplied with water containing a uniform proportion of the salt,
and I have found it convenient to use the salt (whichever of them it may be
5 preferred to employ) in the proportion of one-third of a pound of salt per
month for each horse-power of the boiler. In place of mixing the solution of
the salt with the water in the reservoir from which the boiler is supplied, it
may (although not so advantageously) be introduced at intervals directly into
the boiler. In either case the loose sediment deposited at the bottom of the
boiler should be drawn out, from time to time, by opening the cock, with
which steam boilers are ordinarily fitted for the purpose. When using an
insoluble salt of lead to prevent incrustation in boilers fed with fresh water, I
add the salt at intervals to the water in the boiler, employing, as before, about
one-third of a pound of salt per month for each horse-power. The insoluble
salt which I prefer to employ is the sulphate of lead. For boilers fed with
sea water when employing plumbate or plumbite of potash or soda, I find a
suitable proportion to be about one-fifth of a pound of the salt per twenty-four
hours for each horse-power. And, in this case, I prefer to supply the salt to
the boiler at intervals of six or twelve hours, the sediment having been drawn
off by the blow-off cock just before each quantity of salt is introduced. I
have also found the following composition to be very suitable for boilers fed
with fresh water, viz. :-
Oxichloride of lead, or Turner's yellow
Sand or clay
Chloride of zinc
-
Hydrochloride of zinc
Red ochre
-
100 parts.
-
92
"
I
"
2
39
5
"
In making this composition, the three first-named substances are mixed
together, then the acid is added, afterwards the ochre, and lastly, to ensure the
mixture being complete, the whole is passed through a sieve. The com-
position should be employed in the proportion of one-third of a pound per
horse-power per month, and may be used in the same manner as sulphate or
other insoluble salt of lead. For boilers fed with sea water, the following
composition may be beneficially employed, viz.:-
Sulphate of lead
Oxichloride of lead, or Turner's yellow
Sand or clay
- 100 parts.
-
دو
5
10
"
-
1
"
The three first-named substances should be well mixed together before
Hydrochloric acid

page_text: stirring in the acid. The composition should be employed in the proportion
of one-fifth of a pound per horse-power per twenty-four hours, and should be
applied in the same manner as when plumbate or plumbite of potash or soda
is used in boilers fed with sea water.
In witness whereof, I, the said Eugène Coulon, have hereunto set my
hand and seal, this Tenth day of September, in the year of our Lord
One thousand eight hundred and fifty-eight.
Vitness,
I, Her Britannic Majesty's Vice-Consul
for the City of Rouen, do certify that
Mr. Euge. Coulon appeared before me,
this Tenth day of September, Eighteen
hundred & fifty-eight, & that in my pre-
sence he signed the above document.
Witness my hand & seal of office,
Rouen, 10 September, 1858.