IMPROVED MEANS AND APPARATUS FOR GENERATING ELECTRICITY BY HEAT
Year: 1868

page_text: LETTERS PATENT to Edward Thomas Hughes, of the Firm of Hughes
and Son, Patent Agents, 123, Chancery Lane, London, for the
Invention of "IMPROVED MEANS AND APPARATUS FOR GENERATING
ELECTRICITY BY HEAT."-A communication from abroad by Louis
Mure and Charles Clamond, of Bourg Saint Andéol, in the Empire
of France.
PROVISIONAL SPECIFICATION left by the said Edward Thomas Hughes
at the Office of the Commissioners of Patents, with his Petition, on
the 7th October 1868.
I, EDWARD THOMAS HUGHES, of the Firm of Hughes and Son, Patent
Agents, 123, Chancery Lane, London, do hereby declare the nature, of
the said Invention for "IMPROVED MEANS AND APPARATUS POR GENERATING
ELECTRICITY BY HEAT," a communication to me from abroad by Louis
Mure and Charles Clamond, of Bourg Saint Andéol, in the Empire of
France, to be as follows:-
This Invention relates to a thermo-electrical pile in which a new
substance called galena (pure potter's ore, without either silver or

page_text: galena, being combined with iron by means of a solder specially adapted
for the purpose.
The pile consists of a horizontal circular disc of refractory earth, or
other suitable substance, the said disc being hollow in the centre and
having several rectangular ribs projecting from its surface, and radiating
from its centre, a block of galena having a slight coat or covering of
plaster being placed between each of the said ribs, which may be
also coated or covered with plaster if required. When the galena has
been extracted from the mine it is crushed, placed in a crucible,
worked into a solid mass, and cut into blocks of the required shape
and size by a saw or otherwise. The said blocks are kept in their
proper position on the disc of refractory earth before mentioned by
means of suitable lugs, abutting against the sides of the ribs, projecting
from the surface of the said disc, and between the inner ends of the said
ribs are arranged prisms of iron having shoulders fitting into recesses
in the ribs, the inner edges of the blocks of galena and the outer
edges of the prisms of iron having interposed between each of them
the bent end of a strip or blade of iron which, guided by the radial
projecting ribs, are themselves caused to project radially from the
centre of the disc, and are joined at their outer extremities by solder
or otherwise to corresponding blades or strips of iron in contact with
the outer extremities of the blocks of galena, the inner or bent ends
of the said strips or blades of iron being combined with the galena
and iron prisms by means of a solder, preferably composed of potter's
ore, mixed with about 10 per cent. of sulphuret of copper. On
arranging several of these discs with their component parts one above
the other, and causing flame and other heated products of combustion
to pass up through their central apertures, the prisms of iron will be
highly heated, while the blocks of galena being placed further from
the centre of the discs, and therefore from the heat, and having also
holes directly beneath them, through which a current of cold air is
continually passing, will remain comparitively cool. This difference
of temperature generates the electrical current which passes from the
galena, forming the negative pole of the battery, towards the iron
forming the positive pole of the battery, the electrical circuit being
completed by the strips or blades of iron, joined together at their

page_text: extremities as before stated, one only of such pairs of communicating
points being left out of contact with one another for the escape of
the electricity. The said discs may be kept in position by rods
or pillars, having their upper and lower ends connected to plates,
between which the said discs are placed, or by any other suitable
means.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Thomas Hughes in the Great Seal Patent
Office on the 7th April 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
THOMAS HUGHES, of the Firm of Hughes and Son, Patent Agents, 128,
Chancery Lane, London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of October, in the
year of our Lord One thousand eight hundred and sixty-eight, in the
thirty-second year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Edward Thomas Hughes,
Her special licence that I, the said Edward Thomas Hughes, my
executors, administrators, and assigns, or such others as I, the said
Edward Thomas Hughes, 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 AND APPARATUS FOR GENERATING
ELECTRICITY BY HEAT," a communication to me from abroad by Louis Mure
and Charles Clamond, of Bourg Saint Andéol, in the Empire of France,
upon the condition (amongst others) that I, the said Edward Thomas
Hughes, 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.

page_text: NOW KNOW YE, that I, the said Edward Thomas Hughes, 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 and accompanying Sheet of Drawings
(that is to say) :-
Thermo-electrical piles have not, up to the present time, been
extensively used on account of certain practical difficulties, arising
from their construction, and above all from the nature of the materials
of which they are composed. If, however, the thermo-electrical pile
possesses the advantage over the chemical pile in that it does not
require to be constantly replenished with the agents employed for
producing electricity and in that the considerable expense incurred
in the maintenance of the chemical pile is dispensed with, it is
nevertheless very inferior to this latter pile, as regards the regularity and
the power of the currents developped; besides this the heterogenious
matters of which it is composed, and which are exposed to heat,
although they do not wear away, yet they change their properties
after a certain time, and during the greater part of the time they
are in use they are undergoing a process of oxidation, and therefore
becoming unfit for the production of dynamic electricity. All these
disadvantages have been recognized and considered, and it is with a view
to obviate them that this improved thermo-electrical generator has been
invented.
"
"
The Invention consists in the application of the substance called
galena" or "alquifou (i.e. sulphuret of lead free from either silver
or copper) to the production of electricity by heat, and one of the chief
characteristics of the Invention is the combination of this substance with
iron to form a chemical pile, the said combination being effected by
solder, preferably composed of alquifou mixed with about 10 per cent.
of sulphuret of copper.
In order that this Invention may be clearly understood I will
describe the same with reference to the accompanying Sheet of Drawings,
in which Fig. 1 is a vertical section, and Fig. 2 a plan of the thermo-
electrical generator.
The apparatus is composed of several circular layers of simple
elements, arranged radially from the centre; in the Drawing each
layer consists of twelve elements, and as there are five such layers,

page_text: and
placed one above the other, and numbered respectively 1, 2, 3, 4, and 5
(see Fig. 1), it is evident that the pile is composed of 60 such elements,
but their number as well as the number of the layers may be varied.
Each bar, prism, or element is constructed of blades of sheet iron,
forming the positive pole of the battery, combined with galena prepared
in a special manner, and forming the negative pole of the battery.
The galena used is a sulphuret of lead free from silver and copper,
possessing variable electrical properties, according as it is prepared by
fusion or by agglomeration. In order to obtain greater effect it will
suffice to increase the section of the bars of galena and the thickness
of the blades of sheet iron, for in a thermo-electrical pile the tension
increases with the number, whilst the effect increases with the section
of the bars. The galena is powdered and proto-sulphuret of copper
or iron added thereto, and is then melted and run into moulds, where
the blades of sheet iron have been arranged beforehand; the com-
plete element is then taken from the mould in the form of a prism,
in which the sheet iron is thoroughly united to the galena by the
fusion which takes place in the mould. About th of proto-sulphuret
of iron or copper is generally required to render the galena fusible.
Each bar or prism of galena thus molten and cast generates a great
quantity of electricity, and by agglomerating on the contrary the pure
galena to form the bars greater tension is obtained; by employing
therefore respectively these two processes the electrical effects can be
varied at pleasure.
In the plan, Fig. 2, is seen one of the layers or crowns of the pile,
the galena being in the form of a polygonal slab or plate, the head of
the polygon projecting into the flame which acts upon the positive
element, the outer end of the polygon on the contrary projecting into
the cold air. The sheet iron partially encircles the slab of galena, but
is insulated therefrom by a leaf or blade of mica, or by asbestos united
with silicate of soda. These elements are placed side by side touching
each other at the edge of each polygon, and are also insulated from
each other by mica or asbestos, thus forming a crown of piles through
the centre of which the heat passes. These crowns are arranged one
above the other and separated by intermediate rings of cardboard,
impregnated with silicate of soda, to render them uninflammable. The
pile is enclosed between two rings of iron of the same dimensions as the
rings of cardboard, bolts passing therethrough to keep them in position.

page_text: A is a heating cylinder of metal perforated with holes, so that air
can be mixed with the gas or other flame used for heating it, and it is
placed concentrically in the interior of the pile, and is of the same
height, closed at the top and open at the bottom, it being there provided
with a damper for regulating the admission of air; B is a circular
tube surrounding the heating cylinder A, at its lower end the said tube
being also perforated with holes m, m, from which ignited gas passes
between the two cylinders A and K, by which means the cylinder A
is highly heated, the admission of gas being regulated by a cock on the
tube B; C is the damper for regulating the admission of air to the
heating cylinder A.; D, a sheet-iron tube placed above the pile and
acting as a chimney, for causing a draft up the heating cylinder; E are
prisms of galena forming the negative pole of the battery, and F blades
of sheet iron forming the positive pole of the battery; G are leaves or
blades of mica, insulating from each other the different elements of the
same crown; H, rings of asbestos or cardboard insulating and forming
the spaces between the layers or crowns, and I are copper terminals
insulated from their iron supports by cardboard, and serving the
purpose of accumulating the electricity from the two poles of the
battery, copper wire from each of the poles leading to the said
terminals.
This apparatus will be found to be very economical, all the gas being
consumed in the pile; the jets of gas on account of their contact with
the jets of air entering through the perforations resembling those that
would be formed by a multiple blowpipe. The heat can also be raised
to any temperature, as the upper and lower perforations are the same
size. The action of the apparatus is extremely simple, it being only
necessary to regulate the admission cock and the damper, in order to
obtain any required supply of gas and air; or petroleum may be used
instead of gas, if prefered.
Having now described the nature and particulars of the said Invention,
I claim,-
1st. The arrangement and combination of the thermo-electrical
generator with a heating cylinder, forming a multiple and self-acting
blowpipe, and having crowns or layers of simple elements or prisms
arranged one above the other and radiating from the centre of the pile
as herein described and specified.

page_text: And, 2nd. The composition of each element of galena or alquifou
forming the negative pole of the battery with blades of iron adhering
thereto and forming the positive pole of the battery.
In witness whereof, I, the said Edward Thomas Hughes, have
hereunto set my hand and seal, this Seventh day of April, in
the year of our Lord 1869.
E. T. HUGHES. (L.8.)