Year: 1890

page_text: structure preferably a substance in a diffuse or finely comminuted state, whereby
the potential of said discharge becomes reduced or destroyed substantially as and
for the purpose specified.
There are many forms in which this interposed substance can be applied to the
building to be protected among those I prefer are:
If used as an auxiliary of the lightning rod, a thin box made of non-conducting
material and filled with soot is interposed in the lightning rod about six or eight.
feet above the roof of the building the rod being broken at that point so that the
electricity can pass from that portion of the rod which enters the top of the box to
that portion which emerges from the bottom of the box only by passing through
the soot in same way as soon as the electricity enters a substance of this structure
its particles fly apart, some or all of them being charged with portions of the
electricity and thus the potential of the electricity will be greatly reduced and
probably no further harm will result. This effect of course would depend largely
upon the quantity of soot employed but a cubic foot would probably be found
sufficient for all ordinary cases.
The arrangement just described as one mode of application of my invention is
shown in the accompanying drawing, in which A indicates the gable end of a
dwelling or school-house, B the lightning rod attached thereto, in the ordinary
manner, and suitably insulated, C being the extreme top of the rod and D the
ground into which the rod penetrates to a sufficient depth to allow the electricity
to flow off readily into the earth; E is a box of soot situated at a suitable and con-
venient distance above the peak of the gable, the lightning rod not passing through
the box of soot, but spreading into plates on the top and bottom thereof, and
connected through the soot by fine vertical wires a.
If the lightning rod is discarded and my invention used as the sole protection I
prefer covering the roof with a thin layer of soot or dust or thin metal sheet
properly protected from the weather.
But do not wish to be understood as limiting myself to any particular sub-
stance or form of substance, thus placed in the path of the electric discharge or to
any particular part of said path, but claim to be the first ever to have practically
applied the principle of supplying lightning and other electric discharges with a
substance upon which to expend their force as a protection against their destructive
effects, instead of attempting to lead the same into the ground..
Having-now-particularly-described-and-ascertained the nature of my said inven
tion and in what manner the same is to be performed, I declare that what I
_ claim is :
1. An improved method of protecting buildings etc., from electric discharges
which consists first, in receiving the atmospheric electricity as it collects in the
neighbourhood of said building upon a conducting surface, second, in diffusing said
electricity upon a large surface of finely divided badly conducting substance, third,
shattering said badly conducting substance and thus reducing the charge and lastly
in conducting the residue of said discharge to the ground as and for the purposes
specified.
2. An improved method of protecting buildings etc. from electric discharges
which consists first in receiving the atmospheric electricity as it collects in the
neighbourhood of said building upon-a-conducting-surface-second,-in-diffusing-said
electricity upon a conducting surface of finely divided badly conducting substance,
and lastly in shattering said badly conducting substance and thus reducing the
charge as and for the purposes specified.
Deted this 1st day of December 1890.
NATHANIEL DANA CARLILE HODGES.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.