IMPROVED MEANS OF PREVENTING INCRUSTATION IN BOILERS AND OTHER VESSELS IN WHICH WATER IS HEATED
Year: 1868

page_text: LETTERS PATENT to Charles Weightman Harrison, of Oberstein Road,
Clapham Junction, in the County of Surrey, Gentleman, for the
Invention of "IMPROVED MEANS OF PREVENTING INCRUSTATION IN BOILERS
AND OTHER VESSELS IN WHICH WATER IS HEATED."
Sealed the 17th October 1868; and dated the 24th April 1868.
PROVISIONAL SPECIFICATION left by the said Charles Weightman
Harrison at the Office of the Commissioners of Patents, with his
Petition, on the 24th April 1868.
I, CHARLES WEIGHTMAN HARRISON, of Oberstein Road, Clapham
Junction, in the County of Surrey, Gentleman, do hereby declare the
nature of the said Invention for "IMPROVED MEANS OF PREVENTING
INCRUSTATION IN BOILERS AND OTHER VESSELS IN WHICH WATER IS HEATED,"
to be as follows:-
My Invention consists in combining or connecting by any suitable
means the shell of the boiler or vessel with another body, which in
their electrical relations shall be of a differing or opposite polarity or
condition the one to the other or capable of being rendered so.

page_text: •
One method by which I effect this object in a very simple manner is
by suspending or supporting in the water contained in the boiler or
vessel a plate or body of metal or other suitable electrical conductor, and
attaching it to the shell of the boiler or vessel. The boiler or vessel
forming one electrode, and the suspended or supported plate or body the
other electrode. I so proportion the size between the two that the
electro-chemical action upon the interior surface of the shell of the
boiler or vessel shall be nascent or nearly so, as I find it merely
necessary under ordinary circumstances to impart a positive polarity to
the shell of the boiler or vessel in order to prevent the coherence thereto
of precipitated matters.
In some cases I vary the method of carrying out my improvements
by means of an additional electrical source so arranged as to transmit
alternately positive and negative currents to the shell of the boiler or
vessel and to the suspended or supported body; this arrangement I find
greatly facilitates the production of steam.
My Invention further consists in preventing incrustation in boilers
and other vessels in which water is heated by charging the shell of
the boiler or vessel in any convenient manner with static or current
electricity produced or developed independent of the boiler or vessel and
the liquid therein.
This part of my Invention may be performed by placing the shell of
the boiler or vessel in communication by means of a suitable arrange-
ment with a Leyden jar or the poles of a. galvanic battery. The
intermittent or continuous discharge from which is made to penetrate
the shell of the boiler or vessel, and thereby has the effect of preventing
incrustation. In place of a Leyden jar or galvanic battery. I produce a
similar result by connecting the shell of the boiler or vessel with the
two extremities of a wire carrying an induced or magneto-electric
current.
In order to indicate in any of the foregoing arrangements the force
of the operating electricity and its duration I fix an electrometer upon
the boiler or vessel, and by proper connections bring it within the
electric circuit.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Charles Weightman Harrison in the Great Seal
Patent Office on the 24th October 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
WEIGHTMAN HARRISON, of Oberstein Road, Olapham Junction, in the
County of Surrey, send greeting, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fourth day of April, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
first year of Her reign, did for Herself, Her heirs and successors, give
and grant unto me, the said Charles Weightman Harrison, Her special
licence that I, the said Charles Weightman Harrison, my executors,
administrators and assigns, or such others, as I, the said Charles
Weightman Harrison, 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 "IMPROVED MEANS OF PREVENTING INCRUSTATION IN BOILERS
AND OTHER VESSELS IN WHICH WATER IS HEATED," upon the condition
(amongst others) that I, the said Charles Weightman Harrison, 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 Charles Weightman Harrison, 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:-
It is well known that water always acquires positive electricity in its
friction against solid bodies to which a negative or contrary electricity
is imparted. In this condition the solid body, especially if a good
conductor like one of the metals, becomes susceptible of combining
with or being coated with various of the products that are thrown down

page_text: from water by both the secondary action derived from electricity and
by heat.
Now the purport of my Invention is to obviate this tendency in boilers
and vessels within which water is heated by means of arrangements
or constructions which shall by continuous or intermittent electrical
discharge obstruct or carry away this induced electricity, also by the
medium of a separate electrical source placed in or connected with
the vessel forming the feed water tank to purify the water from much
of the saline or foreign matters that it holds before it passes into the
boiler.
Various modes of carrying my Invention into operation may be devised
several of which I will proceed to describe. The first consists in suspend-
ing from the crown of the boiler or vessel with which it must be in metallic
contact a negative electrode, such as copper when the boiler is as most
usual made of iron, so that it may dip into the water as thus constitute
a galvanic pair of copper and iron electrodes. The effect of this arrange:
ment, if the negative electrode bears an approach in size to that of the
positive electrode, would be to produce in ordinary hot water active
electrolytic action on the iron and promote the ultimate destruction of
the vessel, but as the quantity of electricity passing is less in proportion
as the surface of contact between either of the electrodes and the water
decreases I reduce the size of the copper so that it bears a very minor
proportion to that of the iron the extent of copper immersed in the water
should for the purpose of performing my Invention by this mode of
operating give rise to an electric current which would suffice to indicate
but two or three degrees on a sensitive galvanometer introduced into the
circuit, thereby showing that the electrodes are little more than passively
polarised. In this condition the boiler or vessel throws off or repels any
precipitated matters.
Steam power
boilers may also be protected by a similar arrangement,
the conductor or copper electrode being carried over or around the
flues in any convenient manner, care being observed to avoid contact
between the metals in the water; I mostly prefer, however, to bring the
boiler by suitable connections into the circuit of a continuous electrical
current derived from an additional or separate source of electricity, thus
making the boiler serve as a conductor in which the electricity intro-
duced at one point diseminates itself throughout the whole extent of the
boiler plates or case, and is conveyed away at another or opposite point

page_text: after having during its propagation turned away or withdrawn the
induced electricity. Any suitable additional source of electricity may be
employed for this purpose, and alternate currents of positive and negative
electricity transmitted by proper contrivances the construction of which
is well known to mechanists.
Further my Invention may be performed by connecting the boiler by
means of a conducting wire with an earth plate or electrode buried in moist
ground or with one of the poles, the negative for instance, of a galvanic
battery which is in communication with the ground through its other or
-positive pole, or by other suitable arrangement, and thereby nullify or
more effectually discharge the electricity generated in the boiler, the
escape of which is retarded by the heated air and dry material with
which it is surrounded.
Another further portion of my Invention for the prevention of incrus-
tation relates to the use of an additional electrical source produced or
developed independent of the boiler or vessel and the liquid therein so
arranged as to be able to transmit alternately positive and negative
currents to the boiler or vessel or to the suspended or supported body,
the object being that of turning to account the chemical reactions that
arise from the liberation of a body in its nascent state upon the surface
of contact of a solid and liquid conveying electricity.
This improvement is peculiarly advantageous to the boilers of land
and marine locomotives which have to be kept in long continuous work,
and whether ordinary or saline or condensed water is used; in the latter
case it has the effect of materially obviating the obscure action which
produces corrosive incrustation in boilers fed therewith. It is performed
by placing a number of plates of iron or other form or kind of electrode
within the feed water vessel or tank, they being supported in any
convenient non-conducting frame in such a position that the water
must pass between them. The frame may be made of wood, and grooves
formed therein to hold the plates in position at a short distance from
cach other suitably about half an inch apart. Each plate is connected
with the poles of a galvanic battery or other source of electricity in
such a manner as to be charged at the same time alternately positive
and negative, and to prevent any foreign matter covering or adhering
to the plates the direction of the electric current is reversed by suitable
means, as occasion may require, the negative thereby becomes positive,
and the positive becomes negative electrodes. In place of metal coke

page_text: that has been well washed and dried previously may be used to form
the electrodes, it having the advantages of exposing a large surface by
reason of its porosity and being light in weight; in this case however
the necessary conducting connections in contract with the coke should
be of platinum or thickly platinized wires. The battery most suitable
for this purpose should be capable of evolving electricity in large
quantity, and of sufficient intensity to pass freely through the water
between the plates in the vessel, and the frame holding the plates
should be placed convenient for removal whenever the vessel requires to
be cleaned.
از
In witness whereof, I, the said Charles Weightman Harrison, have
hereunto set my hand and seal, this Twenty-fourth day of
October, in the year of our Lord One thousand eight hundred
and sixty-eight.
C. WEIGHTMAN HARRISON. (L.S.)