Rock Island Argus. (Rock Island, Ill.) 1893-1920, 1914-07-11

se,t some of its contents. She was
released on her own recosnizance until
Monday.
wire of substantial size of the same
style as barbed wire but without the
barbs furnishes very good material
for cheap iron lightning rods. The
presence of the barbs constitutes a
rather serious Inconvenience in hand
7 ling and installing such a conductor,
aud no material benefit is derived from
their presence.
Copper is better than iron not only
on account of its iniestructibility but
also because of its softness and plia
bility which make it easy to install.
Scientists are not in accord in regard
to the relative merits of the electrical
properties of copper and iron, but in
any case questions of cost, durability.
and the life far outweigh minor differ
ences in electrical properties.
Aluminium is a competitor for iron
and copper for lightning rods. Its dur
ability under exposure to weather is in
its favor, but its feasibility makes it in
ferior to iron for points.
If low first cost is the controlling
factor, galvanized-iron rods must be
chosen, but subsequent inspections
must be made and repairs may become
necessary.
If higher first cost is not an obstacle,
the choice should go to copper first or
possibly aluminium.
CD Should lightning conductors be
made in the form of solid rods. fiat
bars or bands, stranded twisted cables,
woven stranded ribbons, or hollow
twisted cables? Answer: Any of the
forms may properly be employed, or
two o. more forms may be employed in
combination. Conductors should be
put up in long continuous pieces as far
as possible. Solid round wires one
quarter to one-half inch in diameter
are best for this purpose Conductors
of a size larger than one-four inch,
however, present difficulties in hand
ling and installation if the rods are
solid. It then becomes better to use
stranded cables and other similar
forms. Long continuous lengths, am
pie cross section combined with fis-xi-
bility and the ease of its installation
over crooked courses render stranded
cables, in general, better than any 9TH
er form of conductor available.
Substantial iron points in combina-
ton with copper cables from. fve-siX-
teenths inch in diameter, for small
farm buildings, to one-half inch in di.
ameter for large important structures
form one of the best possible systems
of conductors for Iightning-rod con-
struction.
There is no good reason for purchas-
ing other fanciful forms of cable at
materially greater prices per pound
than are asked for standard makes of
cable OF approximately the same cross
section.
60 Must lightning rods be connect
ed to the earth? Answer: Yes; by all
means, and most effectively Just
few operators in the lightning rod pro-
fession have sought to impose upon the
uniformed a system of ungrounded
lightning rods. Such rods are a men,
ace instead OF a protection. It is I'M
practicable to fully discuss here meth
DDS of making. connections to earth. In
general terms the conductor should be
carried down into the earth and away
from the building in trench or other
excavation, so as TO reach and imbed |
the conductor itself or plates attached |
thereto into permanently moist earth |
Connections with water pipes or other |
metal work itself connected to earth |
constitute good grounds.
go Are government buildings pro |
vided with lightning rods? Answer: I
Yes; many of them, but naturally not /
every one.
90 Does the government use the 1
material or the rods or the system of I
any particular agency? Answer: No; I
there is nothing mysterious or excep .
tional about lightning rods, the mater
ial of which they are composed, or
their construction and installation I
Suspicion may we'll be aroused as to
the reliability of those making extrav. l
agant claims of superiority for their |
particular wares to the exclusion of i
others.
(10) What is the best arrangement Il
of rods on a building? Answer: A
building completely screened and sur
rounded by and inclosed beneath a
cage or network of substantial metallic |
conductors, all properly interconnect-
ed and Joined to the earth, would be /
most effectively protected from light |
ming discharges. For ordinary pur-l
poses far simpler system is adequate. |
For example, good protection is afford /
ed by conductor running along the /
ridge OF building and extending TO /
the earth, either at the middle of the |
sides or, preferably. at each of the /
four corners. Points should rise above |
any prominent feature of the building, |
such as cfimneys or. in the absence of !
these features. from the ridge OF the !!
roof at intervals of % feet or there |
abouts. Fuller details of lightning rod |
installation are to be found in Farmers |
Bulletin No. 367, new edition of |
which is now in course of preparation. |