The anti-monopolist. [volume] (Saint Paul, Minn.) 1874-1878, 1877-08-02
LIGHTNING RODS

A correspondent Of the Country
Gentleman writes to the editor of that
paper as follows:
"Having read tharecent article in
your journal relative to lightning rods,
l venture to PROFOUND the following
inquiries: Given a large building, say
church with spire, the spire covered
with tin and painted, the church roof
ed with slate, valleys Of copper and
conductors of tin, rod with points
sOldered to the tin roof, the latter con-
nected by strips of copper soldered to
the copper valleys, the tin conductors
connected by strips or rods Of copper
from the bottom with permanent mOis-
tected against lightning! Q) Would
the building be better protected if the
above conductors were attached in the
building to the gas pipes? (2) Does the
paint on one side of the tin materially
reduce it's power of conduction! 81 Is
it not an accepted theory that the
closer the rods are attached to build
ing the better! AZ DO you approve of
the method used for protection of the
Centennial buildings, as explained in
the SCIENTIFIC AMERICAN of about a
month since! ~ w. III. q.
To which the editor Of the Country
Gentleman replies:
l. We do not perceive why this would
not make q good connection through
out, and afford ample protection. The
different connections might be more
liable to become detached in the lapse
of years than firm rod, and would not
need looking to. In case the points
above should prove insufficient to car
ry off silently the fluid from heavily
charged cloud Immediately above. and
there should be an explosion Ia rare
occurrence in such case) there would
be more liability to injure the building
than il the rod were a foot or two dis
tant from the building. 2. Gas pipes,
well connected, would make good con-
ductors, with the same LIABILITY as that
just mentioned. 3. Paint does not re-
duce the conducting power. A. 1t is
better that the rod be short distance
off from the building, for the reason
already explained. 5. We do not know
the mode adopted on the Centennial
! buildings, and have not the paper re-
| ferred to at hand.
REMARKS UPON THE ABOVE ANSWERS.
l-1) We coincide substantially with
the Country Gentleman in respect to
the general sufficiency of the above ex-
amples of protection. The proposed
connections above ground are correct;
but if there is any deficiency, it is in
the underground connections. The
terminal metal of the rod, placed un.
dergr0und, in contact with moist earth
should be as extensive in area as pos.
sible.
We think it erroneous to suppose
that lightning rods are a means of 81
lently discharging the electricity of
thunder clouds. The latter are gen.
orally more than half mile distant a.
bove the earth when the discharge
takes place; and while a properly ar
ranged rod, if struck, will conduct the
electricity safely to ground, the sud-
den leap Of the lightning through this
air space to the rod sets the air into
tremendous vibration, producing
sounds like the roaring of artillery.
Only the atmosphere electricity, close
to the surface of the earth, is conduct
ed to the ground silently by rods,
buildings, trees. etc.
The object of the rod being to con-
duct off electricity from the building
to earth, the rod should consequently