IMPROVEMENTS IN PREVENTING AND REMOVING INCRUSTATION IN STEAM BOILERS
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, MAXA-
MILIAN FRANCOIS JOSEPH DELFOSSE, late of Paris, but now of Regent Street,
in the County of Middlesex, Esquire, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Twenty-fifth day of
August, in the tenth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Maximilian Francois Joseph
Delfosse, my exors, adñiors, and assigns, Her especial licence, full power, sole
privilege and authority, that I, the said Maximilian Francois Joseph Delfosse,
my exors, adñiors, and assigns, or such others as I, the said Maximilian
Francois Joseph Delfosse, my exors, adiñiors, or assigns, should at any time
agree with, and no others, from time to time, and at all times 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,
and in all Her Majesty's Colonies and Plantations abroad, and also in the
Islands of Jersey, Guernsey, Alderney, Sark, and Man, my Invention of
"IMPROVEMENTS IN PREVENTING AND REMOVING INCRUSTATION IN STEAM BOILERS;"
in which said Letters Patent is contained a proviso that I, the said Maxi-
milian Francois Joseph Delfosse, shall cause a particular description of the
nature of my said Invention, and in what manner the same is to be per-
formed, by an instrument in writing under my hand and scal, to be inrolled in
Her said Majesty's High Court of Chancery within six calendar months
next and immediately after the date of the said in part recited Letters
Patent, as in and by the same, reference being thereunto had, will more fully
and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Maximilian Francois Joseph Delfosse, do hereby declare that the nature of
my said Invention, and in what manner the same is to be performed,
are particularly described and ascertained in and by the following Specification
thereof, that is to say:-
Whereas, the waters employed in steam boilers consist commonly of one or
other of three varieties, namely, first, fresh water; second, tidal or brackish
water, composed of a mixture of fresh and salt water; and third, sea water:
and whereas, all these waters contain in a state of solution or suspension, and
in greater or less quantities, a number of foreign matters, of which the chief
are salts of lime in the state of sulphates, carbonates, and silicates, salts of
magnesia in the state of carbonates, chlorates, sulphates, or silicates, or ferru-
ginous salts in the state of sulphates, sulphites, and bi-carbonates; and
whereas, the said matters are precipitated in quantities more or less consider-
able by the evaporation of the water, and attaching themselves to the inner
surfaces of the boilers, soon become indurated and form incrustations or petri-
factions which obstruct the passage of the heat to the water, and not only
retard the generation of steam, but cause a rapid deterioration of the boilers;
now, my Invention consists in adding to the water employed in boilers a
certain anti-petrifying mixture or compound which acts on the precipitable
matters contained therein, in such manner as both to prevent such incrustations
or petrifactions as aforesaid from taking place, and to remove them when they
may happen (from the want of such an antidote) to have been formed. The
constituents of this anti-petrifying mixture or compound are, first, dry tannic
or gallic extract, whether obtained from the bark of the oak and other trees,
or from gall-nuts or roots, or from any other substances containing the same;
second. hydrate of soda, or soda deprived of its carbonic acid; third, muriate
of soda; and, fourth, sub-carbonate of potash. I vary the proportions in which
these ingredients are employed in the formation of my said anti-petrifying
mixture, as also the quantity of the mixture used in each case, according to
the degree of impurity possessed by the water (a point easily ascertainable by
previous analysis or trial), and according also as the boiler is stationary or
locomotive. Supposing the boiler to be a stationary one, and that it is fed
with fresh water, a quantity of my anti-petrifying mixture equal to three
hundred and thirty-six hours consumption per horse power, or twenty-eight
days consumption per horse power, reckoning the working hours at twelve per
day, may be formed as follows, viz, of twelve ounces of muriate of soda, two
and a half ounces of bydrate of soda, two drachms of the dry tannic or gallic
extract, and half an ounce of sub-carbonate of potash. If there should be an

page_text: admixture of salt water in the boiler, then I leave out the muriate of soda, and
make use of six ounces instead of two and a half of the hydrate of soda, and
of five drachms instead of two of the dry tannic or gallic extract. For loco-
motive boilers, travelling on an average about one hundred and forty miles per
day, I increase the quantity of the compound per horse power by about one
fifth. Where sea water is employed, I modify the compound in the same way
as when it is applied to a mixture of salt and fresh water. In the case of
locomotive and marine boilers, I prefer adding the mixture daily in portions
corresponding to the amount of duty to be performed each day, and in the
case of stationary boilers, I prefer introducing it in quantities equal to two,
three, or more days of consumption at a time, according to the degree of purity
of the water employed. It may be introduced directly into the boilers of
stationary engines, or, in the case of marine engines, either into the feed tanks
or boilers, but in the case of locomotive boilers, it is better to add it each day
to the water in the tender.
And having now described the nature of my said Invention, and the manner
in which the same is to be performed, I declare that I do not limit myself to the
use of any of the ingredients aforesaid in the precise proportions before stated.
But that what I claim is, the employment for the prevention and removal of
incrustations or petrifactions in steam boilers, of the anti-petrifying mixture
before described, and of any analogous mixture containing for its principal or
essential ingredients fixed alkaline matter combined with gallic or tannic
extract.
In witness whercof, I, the said Maximilian Francois Joseph Delfosse,
have hereunto set my hand and seal, this Twenty-fifth day of February,
in the year of our Lord One thousand eight hundred and forty-seven.
M. F. J. (L.s.) DELFOSSE.
AND BE IT REMEMBERED, that on the Twenty-fifth day of February,
in the year of our Lord 1847, the aforesaid Maximilian Francois Joseph
Delfosse came before our said Lady the Queen in Her Chancery, and
acknowledged the Specification aforesaid, and all and every thing therein con-