The Saint Paul globe. (St. Paul, Minn.) 1896-1905, 1899-12-31
RISK TO STEEL BEAMS
MODERN OFFICE BUILDINGS MAY
BE ENDANGERED BY HIGH POW
Err ELECTRIC CURRENTS
SAYS AN EASTERN ENGINEER

necr ClauSSen and the local electric COM
panles as to cicctrnlysis and its effects
or the subterranean piping of the city
lends special interest to an article in the
January number Of the Popular Science
Monthy,in which the dangers of electrol-
ysis are discussed by Herbert S. Wyn-
FoOp, under the title of Effects of Va
grant Electricity" Some of the explana-
tions given are clearer than any which
have been vOuchsafed in other than the
most technical publications. Mr.. Wyn-
koop writes:
Hidden beneath out highways lie gas
pipes. water pipes, Edison tubes and
Iead-covered cables. These are the cleo
trodes. In contact with these conductors
Is the soil containing an electroiyzable
salt chloride, nitrate or suiphate of am
monia, potash, or magnesia, generally
In the presence of moisture this salt be-
comes an electrolyte, or salt solution.
In the absence of electricity no appre-
cable damage occurs; but the passage
Of an electric current, however small,
from one pipe to another is sure sooner
or later to leave its traces upon the posi-
tive conductor in the form of a decay
other than mere oxidization. 1t is to this
decay that has been given the name cleo
trolysis; SO that when this heading ap-
pears in the daily press, or in technical
journals, one may interpret the term
popularity as the electrolytic corrosion
of metals buried in the SOIL
ITO produce electrolytic disintegration
of pipes, etc, on a scale grand enough
to cause apprehension, a bountiful source
Of electricity Is essential Unfortunately
this condition is not lacking today in any
town in which the usual overhead trolley
electric railway is in operation. This
system of propulsion is based upon the
use Of a ground return-that is. the
electricity passes out Of the power house
to the bare trolley WIRE then to the pole
on the roof Of the car, thence through
the motors to the wheels, whence it is
expected to return to the power house
Via the rails. AS a matter of fact how
ever, the released electricity by no means
confines Itself to the rails and the copper
return feeders. 1t avails itself of all
underground electrical conductors, includ-
ing subterranean water courses, sewers
and metallic earth veins"
Mr. Wynk0op's article IS ACCOMPANIED
by Illustrations showing iron and lead
pipes after exposure to electrolysis He
writes that dry, sandy soils tend to keep
down the flow Of current by interposing
a high resistance, so that in such locali-
ties electrolytic effects are not as pro-
noUnccd as in wet, loamy soils. The
coating of the pipe may be q partial bar
rier to check the passage of the electricity
also. Until recently it was supposed that
cast iron was not affected, seriously
enough, at least, to cause alarm, and re-
cults at Brooklyn, where tests of some
severity were made, tended to confirm
this belief, until, according to Mr.. Wyn-
koop, $1,000 damage was discovered to
have already been done at Dayton, O.
A popularity of cast iron electrOysiS is
that the original shape is retained, the
iron being eaten out of the graphite
which remains as shell.
In order to avoid any suspicion that
he is attacking the trolley lines Mr. Wynn
koOp states:
There seems to be mistaken impress
sion abroad that the railway companies
are Indifferent on this subject. So far
as my experience and information go
this is not the case. They are only too
anxious TO find q remedy-not, as some
electricians have stated, to save their
coal pile, for energy is wasted in forcing
the electricity back to the power house,
no matter what the path, but because
they fear that at some future Date the
taxpayer, the corporation and the munich
pality will band together, present over
whelming bills for damages and sweep
the trollcys off the face CT the earth.
The instinct of seIf-preservation, il moth
ing else, demands that the electric rail-
way companies should put forth every
endeaVor tC solve the electrOlysis prob
lem.
while we may not care how extensive
ly or how frequently the city authorities
or the private corporations are obliged
to renew their under ground metals, we
are at least vitality concerned as to
whether the stray electricity is endanger-
Ing our steel office buildings, our bridges,
[dr water supply, our immunity from
CONGREGATIONS and the safety Of the 101
appliances that go to make up our mod
ern civilization"
Locally, as nearly as can be learned,
the situation has not changed materially
since City Engineer Claussen instituted
his recent correspondence with the vari-
Dus electric companies.
In St. Paul the custom, as nearly as
anything can be learned about the prac-
tice of the companies, is for those hav-
Ing underground cables to bind them
TO the rails of the street railway at in
tervals by means of g copper wire. This
practice, while not entirely successful, has
helped to a considerable extent; SEEM
ingly, though, If Engineer Wynkoop's
Ideas are correct, this can only serve to
protect the points directly connected, and
at any point where the cable is in wet
ground the electrolysis is sure to occur
to some extent, despite this precaution in
his opinion
The suggestion has been made here that
the city waterworks department, which
has experienced some difficulty with cleo
trclysis already, bind its mains similarly
TO the rails Of the company
Another danger which exists in cities
10 a greater or less extent, exactly how
widespread such connections are being
hard to say, IS the connecting Of old-time
telephone and telegraph connections with
water or gas pipe for ground" This
was formerly a common practice before
the powerful electric light and trolley car
plant currents became of such universal
extent in cities, and the electricians be-
came aroused to a sense Of the dangers
existing therein.
But how generally II was practiced q
few years ago may be judged from the
following quotation for instructions to
operators" in a manual of electricity for
students and users Of electricity, by one
considered In his time an authority:
mo better ground can be secured than
the iron water pipe of a town or city,
and this should, II possible, be always
secured. An iron gas pipe will, however,
serve a very good purpose provided the
connection be made outside Of the meter;
this preeaution is necessary because the
meter is sometimes removed and hecause