IMPROVEMENTS IN LIGHTNING ARRESTERS FOR PROTECTING ELECTRIC TELE- GRAPH APPARATUS
Year: 1864

page_text: LETTERS PATENT to David Augüste Burr, of Washington City, United
States of America, now of No. 12, Southampton Buildings, Chancery
Lane, in the County of Middlesex, Civil Engineer, for the Invention of
"IMPROVEMENTS IN LIGHTNING ARRESTERS FOR PROTECTING ELECTRIC TELE-
GRAPH APPARATUS."-A communication from abroad by George Stearns,
of Rochester, New York, United States of America.
Sealed the 29th April 1864, and dated the 16th January 1864.
PROVISIONAL SPECIFICATION left by the said David Auguste Burr at
the Office of the Commissioners of Patents, with his Petition, on the
16th January 1864.
I, DAVID AUGUSTE BURR, of Washington City, United States of America,
now of No. 12, Southampton Buildings, Chancery Lane, in the County of
Middlesex, Civil Engineer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN LIGHTNING ARRESTERS FOR PROTECTING ELECTRIC TELE-
GRAPH APPARATUS" (a communication) to be as follows:-
These improvements relate chiefly to the employment of charcoal, powdered
glass, sulphur, amber, or their equivalents as electric conductors for separating
and discharging atmospheric electricity from the wire circuits of telegraphic
lines. The charcoal, powdered glass, orther equivalent substances are placed
between metallic plates, the upper one of which is made to form a part of the
line circuit of the telegraph by connecting the ends of the wires to either end
of said plate by means of suitable binding posts. To the lower plate is united

page_text: a large wire communicating with the ground. The charcoal may be used either
pulverized or solid. If used solid the grain of the wood should be placed at
right angles to the plates. Fine metallic points may be advantageously placed
in the charcoal, the said points touching the lower and extending nearly to
the upper plate of the "paratonnerre." Charcoal, powdered glass, sulphur, and
amber, or their equivalents in this connection being good conductors of atmo-
spheric electricity, and comparatively imperfect conductors of voltaic electricity,
are thus made to separate and discharge atmospheric electricity from the
line conducting the voltaic current, the latter being left to follow the wires
unchecked and undisturbed.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said David Augüste Burr in the Great Seal Patent Office on the
14th July 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
AUGUSTE BURR, of Washington City, United States of America, now of
No. 12, Southampton Buildings, Chancery Lane, in the County of Middlesex,
Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixteenth day of January, in the year of our Lord
One thousand eight hundred and sixty-four, in the 27th year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the
said David Augüste Burr, Her special license that I, the said David Auguste
Burr, my executors, administrators, and assigns, or such others as I, the said
David Auguste Burr, my executors, administrators, or assigns, should at any
time agree with, and no others, from time to time and 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 "IMPROVEMENTS IN
LIGHTNING ARRESTERS FOR PROTECTING ELECTRIC TELEGRAPH APPARATUS," a com-
munication,.. upon the condition (amongst others) that I, the said David
Auguste Burr, my executors or administrators, by an instrument in writing
under my hand and seal, or under the hand and seal of one of them, 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 imme
diately after the date of the said Letters Patent.

page_text: NOW KNOW YE, that I, the said David Augüste Burr, 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 accompanying Drawings.
making a part of this Specification:-
These improvements relate chiefly to the employment of charcoal, powdered
glass, powdered sulphur, powdered amber, or their equivalents as electric
conductors for separating and discharging atmospheric electricity from the
wire circuits of telegraphic lines.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a plan or top view of the lightning arrester or parratonnerre ;.
Figure 2 is a plan of the same with the upper or circuit plates removed,
showing the position of the lightning arresting substance; Figure 3 is a front
end elevation of the apparatus; Figure 4 is a side elevation of the same;
Figure 5 is a section through the line x, x, of Figure 2; Figure 6 is a plan
of a lightning arrester or paratonnerre of a modified form; Figure 7 is a front
elevation of the same. Like letters refer to corresponding parts in all the
Figures.
66
The frame A of the arrester or paratonnerre is made of wood or other
suitable material in any convenient form or size. Solid pieces of charcoal B
are placed within the frame A between the metallic plates C, C, and D, as
clearly shown in Figure 5. The upper plates C, C, and the lower plate D
are screwed down at their edges upon the frame A, as seen in Figure 1, so as
to cover its central spaces. Ordinary binding posts" or pillars b, b, are
screwed down through apertures in one end of the plates C, C, near the edges
thereof into the frame. Similar binding posts 6, 61, are screwed into the
opposite end of the upper surface of the frame beyond the edges of the
plates C, C, with which, however, they are connected by means of small
platinum wires secured to the one and the other, all as illustrated in Figure 1.
The ends of the wires from the main line are secured in the binding posts b, b,
by suitable binding screws, and the ends of the wires extending to the
recording instruments and magnets are held in the same manner in the
opposite binding posts 6, 6. The connection between these wires is formed,
and the main "line circuit" of the telegraph rendered complete by the inter-
mediate brass plates C, C, and the platina wires a, a, as shown in Figure 1.
The copper plate D, which covers the lower side of the frame, is connected
directly with the earth by means of a large wire or chain. The charcoal (or
other equivalent material) B placed in the spaces of the frame between

page_text: the upper plates C, C, and the lower plate D, as seen in Figure 5, forms a
superior conductor of atmospheric electricity from the plates C, C, to the
plate D, from which it is led to the earth by the large ground wire. In order
to obtain symmetry in the paratonnerre a tongue from the plate D is extended
and bent up over the end of the frame, as shown in Figure 3, and the binding
post E, which holds the earth wire, is screwed into the top of the frame
through this portion of the plate, as seen in Figure 1. The charcoal, which is
placed between the upper and lower metallic plates C, C, and D, may be used
either pulverized or solid; if used solid, as shown in the Drawings, the grain
of the wood should be placed at right angles to the plates, and in this case
fine metallic points may with advantage be fixed in the charcoal, so that their
ends shall extend up so as almost to touch the upper plate, without, however,
coming in positive contact therewith, as illustrated in Figure 5. Powdered
glass, powdered sulphur, powdered amber, or other substances possessing
similar conducting properties may be substituted for the charcoal B.
The paratonnerre, illustrated in Figures 6 and 7, is made to receive but
one set of circuit wires, and has but one cavity for the intermediate charcoal
filling between the upper circuit plate and the lower discharging plate.
The object of this Invention is to protect the apparatus upon telegraph lines
from the evil effects of an excess of atmospheric electricity upon said lines by
separating and discharging this electricity from the telegraph wires to the
earth without interrupting or interfering with the current of voltaic electricity
passing over the same.
In the instrument herein-before described, the voltaic current from the
distant stations arriving in the direction illustrated by the arrows in Figure 1,
will pass directly on across the brass plate C, which completes the metallic
circuit of the main line, and so through the platinum wire a on to the recording
instruments and magnets. If, however, a current of atmospheric electricity
following the wires arrives at the plate C, the small size of the platinum wire
will obstruct it (although allowing free passage to the voltaic current), and
at the same time the charcoal (or its equivalent, as described) will present a
most excellent conductor, which will at once divert and lead it off through the
lower plate D to the large earth wire, which will carry off and dissipate it.
The superior conducting power of the charcoal will thus protect the small
arresting wires a, a, which would otherwise be melted.
Having thus fully described the nature of my improvements, and shown
how the same may be conveniently carried into effect, I wish it understood
that I do not confine myself to the exact details herein set forth; but what I
claim as my Invention is, the mode of separating and discharging atmospheric

page_text: electricity from the wires forming telegraphic circuits by the use of charcoal,
powdered glass, powdered amber, powdered sulphur, or other substances
having similar conducting powers, all substantially as herein described.
In witness whereof, I, the said David Auguste Burr, have hereunto set
hand and seal, this Ninth day of June, in the year of our Lord
One thousand eight hundred and sixty-four.
my
DAVID A. BURR. (L.S.)