IMPROVED MODES OF PROTECTING IRON BOILERS, TANKS, AND VATS FROM WEAR ARISING FROM GALVANIC ACTION
Year: 1862

page_text: LETTERS PATENT to George Tomlinson Bousfield, of Loughborough Park,
Brixton, in the County of Surrey, for the Invention of "IMPROVED MODES
OF PROTECTING IRON BOILERS, TANKS, AND VATS FROM WEAR ARISING FROM
GALVANIC ACTION."-A communication from abroad by John Welton
Wilcox, residing at West Roxbury, in the County of Norfolk, and State
of Massachusetts, in the United States of America.
Sealed the 5th August 1862, and dated the 19th February 1862.
PROVISIONAL SPECIFICATION left by the said George Tomlinson Bousfield
at the Office of the Commissioners of Patents, with his Petition, on the
19th February 1862.
I, GEORGE TOMLINSON BOUSFIELD, of Loughborough Park, Brixton, in the
County of Surrey, do hereby declare the nature of the Invention for "IMPROVED
MODES OF PROTECTING IRON BOILERS, TANKS, AND VATS FROM WEAR ARISING FROM
GALVANIC ACTION," to be as follows:-
This Invention has for its object, firstly, the preventing the galvanic action
which is produced in iron boilers, tanks, and: vats, by their connection with
pipes, pumps, condensers, faucets, or other fixtures of brass, copper, or other
metals electro-negative to iron; this is done by the use of insulating joints
made by introducing between the two metals at every place were they other-

page_text: wise would come in contact a packing of india-rubber or other non-conducting
substance.
Secondly, the Invention has for its object the arresting and depositing from
the water before it is admitted to the boiler, tank, or vat, any copper, or it
may be other metallic salts held in solution by it, and which it may have taken
up by contact with copper or brass as would happen when the water-had
passed through a surface condenser; and in other cases this is done by passing
the water before it enters the boiler, tank, or vat through a vessel containing
zinc in small pieces or its equivalent in galvanic properties on which the
copper or other metal negative to iron, will be deposited so that it may not
be carried into the boiler or tank to produce there a galvanic action so
destructive to the iron vessel.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George Tomlinson Bousfield in the Great Seal Patent Office
on the 19th August 1862.
120
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
TOMLINSON BOUSFIELD, of Loughborough Park, Brixton, in the County of
Surry, send greeting...
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of February, in the year of our
Lord 1862, in the twenty-fifth year of Her reign, did, for Herself, Her heirs
and successors, give and grant unto me, the said George Tomlinson Bousfield,
Her special license that I, the said George Tomlinson Bousfield, my executors,
administrators, and assigus, or such others, as I, the said George Tomlinson
Bousfield, 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 of "IMPROVED MODES OF PROTECTING
IRON BOILERS, TANKS, AND VATS PROM WEAR ARISING FROM GALVANIC ACTION,"
a communication to me from abroad.by John Welton Wilcox, a person resident
at West Roxbury, in the County of Norfolk, and State of Massachusetts, in
the United States of America, upon. the condition (amongst others) that I, the
said George Tomlinson Bousfield, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and seals,
1

page_text: 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 calender months next
and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said George Tomlinson Bousfield, 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, reference being had to the Drawings hereunto annexed,
and to the letters and figures marked thereon (that is to say):-
This Invention consists, firstly, in interrupting the galvanic action, which is
produced in iron boilers, tanks, vats, &c. by their connection with pipes, pumps,
condensers, faucets, or other fixtures of brass, copper, or other metals electro-
negative to iron; by the use of insulating joints by which the two metals are
separated by a packing of india-rubber or other non-conducting substance.
Secondly, in arresting and depositing from the water before it is admitted to
the boiler, tank, or vat, the copper or other metallic salts held in solution by it
and which it has taken up in its contact with the copper or brass fixtures through
which it has passed, by first passing the water through a vessel containing
zinc in small pieces, or its equivalent in galvanic properties, on which the
copper or other metal negative to iron will be deposited, and not be carried
into the boiler or tank to produce there a galvanic action so destructive to the
iron vessel.
That others skilled in the art may understand and use this Invention, I will
proceed to describe the manner in which it has been carried out.
In the accompanying Drawings Figure 1 is a perspective view, and
Figure 2 a longitudinal section of two pieces of pipe connected by an
insulating joint. The pipes A and B have their flanges a, b, separated by a
packing c of rubber cloth. The bolts C which secure the flanges together
are covered with a tube or sleeve of rubber d, the nuts e, by which these bolts
are tightened up rest on a metal washer D, which is separated from the
flange a by a ring f of rubber cloth. The washer D is a ring which may be
cut in two pieces for the convenience of putting on, it does not come in contact
with the pipe A; but there is a space g between them as shown in Fig. 1.
I do not wish to confine myself to the precise construction of this joint, as it
may be varied to suit the position and form of the parts to be insulated,
without departing from the spirit of the Invention.
Figure 3 is a perspective view, and Figure 4, a vertical section of the vessel
employed in carrying out the second part of this Juvention. I will, however,

page_text: state that its form and capacity may be varied to suit the circumstances under
which it is used. E is a tank or vessel to be filled or nearly filled with zinc
in the form of shot or small bullets h. A plug or tap i serves to introduce the
bullets, and another plug k to withdraw them when it becomes necessary to
clean them; this should be done whenever the zinc becomes foul, which in
some waters will be perhaps once in twenty-four hours, and in others once in
thirty or forty days, depending of course on the quantity of water used, and
the amount of metallic salts injurious to iron which the water may contain.
This much can be stated with certainty, that water (at the temperature usually
received from a surface condenser) containing half an ounce of salts of copper
to the gallon can be completely freed from the copper which it contains, in
about ninety seconds, that is, the tank should be of such a capacity that its
contents will be ninety seconds in passing through and in contact with the zinc.
I do not mean by this statement that it is usual for the water coming from the
condenser to contain so large an amount of metallic salts, but only to give the
result of experiments as to the time required in an extreme case. The zinc
bullets may be cleansed by shaking them in a basket, box, or revolving cylinder
for about five minutes, and then rinsing them with water. The water to be
purified is admitted at one end of this tank E as at 7, and passes off from the
other end by the outlet m. The tank should be so placed that the water
coming from the surface condenser (where one is used) or from pumps or pipes
where it has been in contact with surfaces of copper or brass, or other metal
negative to iron, shall pass through this tank in contact with the zine on which
it will deposit in a-metallic state the copper or other metal held in solution by
or suspended in the water. The dimensions of the tank E and the amount of
surface of zinc contained within it which will be required, will depend on the
quantity of water to be passed through it and the amount of metallic salts
contained in the water.
Among the sources of galvanic action which are destructive to steam boilers,
tanks, or vats, of iron may be enumerated all the copper, brass, or other
metallic surfaces negative to iron, in the form of steam or water pipes, pumps,
condensers, faucets, and other fixtures. In the so called "surface condenser "
a large amount of copper or brass is used for the chilling and condensing
surface, from the action of which is evolved much thermo-electricity which is
an active agent in producing the copper salts above described, and the same
water being used over and over again the copper is constantly taken up in
solution and carried in the form of salts into the boiler by the returning water,
and the water again passing off from the boiler to the condenser in the form of

page_text: steam, leaves in the boiler all the salts which it is constantly carrying into it,
thus constituting the boiler the medium of its own destruction by making it a
galvanic battery, and the metallic connection of such condensers with the
boiler and engine cylinder should be broken by the use of insulating joints as
above describod, the joint being placed as near the chilled section as possible,
so as to disconnect as much of the heated metal from the chilled as is
practicable.
I am aware that zinc has been used for the preservation of iron, and has
been placed inside of iron steam boilers to protect them from incrustation, &c,,
but zinc so placed inside of a boiler where the salts of copper exist in solution
becomes an agent of mischief instead of a protector; for it is plain that zinc so
placed will soon become coated with metallic copper, thus forming a negative
plate or surface and at once establishing a galvanic current or action on such
portions of the boiler as remain positive. Some particles of copper will become
detached from the zinc and falling to the bottom will form a precipitate of
metallic copper; and again the copper will not all reach the zine, a portion
will be precipitated on the iron in the form of metallic copper, the same as if
no zinc were near, making it evident that the safest method is to keep the
salts of copper and of other metals injurious to iron out of the boiler altogether.
I am also aware that it is common to precipitate metals from water holding
them in solution, by the introduction into such water of other metals, or of
other metallic salts; but I do not know of water having been so treated on its
passage from the condenser, or the pumps or pipes to the boiler of a steam
engine or other iron tank or vessel.
By the employment of the insulating joints as above described, the surface
condenser will be protected from the thermo-electric current which was the
principal source of its deterioration when in connection with the iron boiler
or the cylinder; and this in connection with the filtration or purifying of the
water from the metallic salts held by it, will prevent the galvanic action in
the iron boiler or tank, which has heretofore been so destructive to it. And
to cut off the galvanic current, the insulated joints should be. introduced
between the iron boiler, and all pipes or other fixtures which are made of
copper or brass.
Having now set forth the nature of this Invention, and explained the manner
of carrying the same into effect, I wish it to be understood that under the
above recited Letters Patent, I claim, interrupting the galvanic action which
is produced in iron boilers, tanks, vats, &c., by their connection with pipes,
pumps, condensers, faucets, or other fixtures of brass, copper, or other metals

page_text: electro-negative to iron, by the use of insulating joints, by which the two
metals are separated by a packing of india-rubber or other non-conducting
substance.
Second, I claim purifying the water before it passes into the boiler, tank, or
other iron vessel, of the copper or other metallic salts which it may hold, by
passing it through a vessel containing zinc or its equivalent in galvanic
properties, substantially in the manner and for the purpose specified.
In witness whereof, I, the said George Tomlinson Bousfield, have
hereunto set my hand and seal, this First day of August, in the year
of our Lord One thousand eight hundred and sixty-two.
GEO. T. BOUSFIELD. (L.S.)