AN IMPROVED METHOD OF PREVENTING OR COUNTERACTING INCRUSTATION IN STEAM BOILERS OR APPARATUS FOR IMPARTING HEAT TO LIQUIDS
Year: 1871

page_text: LETTERS PATENT to Edward Field, of Chandos Chambers, Adelphi,
in the City of Westminster, Consulting Engineer, for the Invention
of "AN IMPROVED METHOD OF PREVENTING OR COUNTERACTING INCRUSTATION
IN STEAM BOILERS OR APPARATUS FOR IMPARTING HEAT TO LIQUIDS."
Scaled the 22nd September 1871, and dated the 1st April 1871.
PROVISIONAL SPECIFICATION left by the said Edward Field at the
Office of the Commissioners of Patents, with his Petition, on tho
1st April 1871.
I, EDWARD FIELD, of Chandos Chambers, Adelphi, in the City of
Westminster, Consulting Engineer, do hereby declare the nature of
the said Invention for "AN IMPROVED METHOD OF PREVENTING OR COUNTER-
ACTING INCRUSTATION IN STEAM BOILERS OR APPARATUS FOR IMPARTING HEAT TO
LIQUIDS," to be as follows:-
My Invention has for its object the prevention of incrustation in
steam boilers or apparatus for imparting heat to liquids by the
application of electricity to such steam boilers or apparatus, and consists

page_text: in causing currents of electricity to pass from the shell or body of the
boiler or apparatus to a suitably placed negative electrode, that is, an
electrode which is connected with the more oxidizable or positive plate
of a suitable battery. For this purposo I use a galvanic or voltaic
battery, and cause its negative electrode to pass thro' the shell or body
of the boiler or apparatus, and protrude into the water or liquid con-
tained therein, taking care to completely insulate the wire of the negative
electrodo from the shell or body of the boiler thro' which it passes, and I
connect the positive electrode, that is, the electrodo which is connected
with the less oxidizable or negative plate of the battery, to the exterior
of the shell or body of the boiler or apparatus, the connexion being
made by preference at a point as remote as possible from the position of
the negative electrode. The battery employed may be either a simplo
battery or a compound battery, according to the intensity required. In
some cases alkali or other chemicals which will not act injuriously on
the iron or metal of the steam boiler or apparatus may be advantageously
mixed with the water or liquid introduced into the boiler for the purpose
of increasing its conductivity and of promoting and aiding the active
operation of the electric currents in preventing and counteracting the
incrustation of the interior surface of the boiler. ·
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Field in the Great Seal Patent Office on
the 30th September 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
FIELD, of Chandos Chambers, Adelphi, in the City of Westminster,
Consulting Engineer, send grecting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of April, in the year of
our Lord One thousand cight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Edward Field, Her special licence
that I, the said Edward Field, my executors, administrators, and assigns,
or such others as I, the said Edward Field, my executors, adminis-
trators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein

page_text: expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, thẻ Channel
Islands, and Isle of Man, an Invention for "AN IMPROVED METHOD OF
PREVENTING OR COUNTERACTING INCRUSTATION IN STEAM BOILERS OR APPARATUS
POR IMPARTING HEAT TO LIQUIDS," upon, the condition (amongst others)
that I, the said Edward Field,. 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 Edward Field, 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 thereof, that is to say :—
My Invention has for its object the prevention of incrustation in
steam boilers or apparatus for imparting heat to liquids by the ap.
plication of electricity to such steam boilers or apparatus, and consists
in causing currents of electricity to pass from the shell or body of the
boiler or apparatus to a suitably placed negative electrode, that is, an
electrode which is connected with the more oxidizable or positive plate
of a suitable battery. For this purpose I use a galvanic or voltaic
battery and cause its negative electrode to pass through the shell or
body of the boiler or apparatus, and protrude into tho water or liquid
contained therein, taking care to completely insulate the wire of the
negative electrode from the shell or body of the boiler through which it
passes, and I connect the positive electrode, that is, the electrode which
is connected with the less oxidizable or negative plate of the battery
to the exterior of the shell or body of the boiler or apparatus. The
battery employed may be either a simple battery or a compound battery
according to the intensity required.
And in order that the manner of performing my Invention may be
fully and clearly understood, I have hereunto annexed two Sheets of
Drawings, in which Figure 1 (Sheet 1) represents a longitudinal section
of a Cornish boiler with my Invention applied to it; Figure 2 shows a
transverse section of the same; Figure 3 (Sheet 2) is a full size vertical
section of part of the boiler-plate, showing the means I prefer to adopt.

page_text: for insulating the negative electrode from the shell or body of the boiler,
and Figure 4 is a plan of the tightening flange and socket of the
insulating apparatus.
-
.
a is the cell of a battery of the kind known as a constant gravitating
battery. This cell contains a galvanic pair consisting of a zinc or 5
"positive" plate b and a copper or "negative plate c.. In carrying
my Invention into practice I have found that for a ten-horse power
boiler as shown working with Thames water as supplied by the South-
wark and Vauxhall Water Company, a superficial area of about 20
square inches in each of the plates b and c gives very satisfactory results. 1
The cell a is filled with suitable electro-motive liquid, preferring to.
use a solution of sulphate of copper; b' is the negative electrode,
consisting of a copper rod connected by the wire b' with the positive
plate 6 of the battery. This electrode 6' passes through the shell or
body of the boiler d, and is curved or bent as shown in Figure 2, so. 1
as to protrude into the water w without coming into contact with
the shell or body of the boiler. For the purposes of insulating the
negative electrode 6' from the shell or body of the boiler, and of making
the metallic connection between the positive electrode c¹ and the shell
or body of the boiler, I prefer to employ the arrangement of apparatus 2
shewn full size in Figures 3 and 4, and to a reduced scale in Figures 1
and 2, it consists of a cast-iron socket e screwed into the shell or body
of the boiler d without cement, so as to ensure perfect metallic contact,
and is provided with a tightening flange or cover e¹, the socket e contains
a porcelain or other insulator f formed with a hole through which the 2
negative electrode 6 passes down into the water. Another similar
insulator is placed above the insulator f, and between these two
insulators I interpose an india-rubber ring or washer to make a
tight joint and prevent any escape of steam from the boiler. The
insulators ff, and washer f, are held down by means of tightening a
bolts e, passing through the flange of the socket e and through the
tightening flange or cover e¹, but in the position of the parts as shewn
in Figures 2 and 3 the insulators are not screwed down; 7º is a brass
or gun metal clip screwed on to the end of the negative electrode b¹ for
the purpose of connecting it to the negative wire b³, but I do not confine ;
myself to this mode of making the connection as it may obviously
be done in other ways, for instance, by passing the wire through a
hole and twisting it round the electrode as shewn in Figures 1 and 2,
or in other well-known ways; the positive electrode c³ is in this case

page_text: connected with the socket e by means of a holding screw e³, thus placing
it in metallic connection with the shell or body of the boiler d, but I
do not confine myself to this particular mode of making such connection
as the positive electrode or wire may in some cases be attached either
directly or otherwise to the shell or body of the boiler or other vessel
to which it is applied without departing from the peculiar character
of my Invention.
It will be evident that my Invention as herein described is applicable
to other kinds of boilers and apparatus for imparting heat to liquids.
"
And having now described the nature of my said Invention and in
what manner the same is to be or may be performed or carried into
practical effect I would have it understood that I do not claim the
precise mechanical arrangements for carrying the same into effect as
herein-before described, nor do I confine or limit myself to the precise
arrangements shewn in the Drawings, so long as the distinctive character
of my Invention is retained, but what I consider to be novel and original
and therefore claim as the Invention secured to me by the herein-béforo
in part recited Letters Patent is, the peculiar method of preventing or
counteracting incrustation in steam boilers or apparatus for imparting
heat to liquids by connecting the positive electrode of a battery with
the shell or body of the boiler or apparatus, and passing the negative
electrode through the said shell or body, but insulated therefrom, and
causing such negative electrode to protrude into the water or liquid
contained in the boiler or apparatus substantially as described.
In witness whereof I, the said Edward Field, have hereunto sct
my hand and seal, this Thirtieth day of September, in the year
of our Lord One thousand eight hundred and seventy-one.
0
Witness,
W. LLOYD WISE,
Patent Agent,
London, W. C.
EDWARD FIELD. (L.S.)