Evening star. [volume] (Washington, D.C.) 1854-1972, 1894-02-28
ELECTRICIAN i'll VAIL ON THE TROLLEY
Continuation Of the Important Con.
vention of Electric Lighters.
THE UNDERGROUND SYSTEMS

tons, though a paper by Mr.. Vail of New
York was of general interest, especially
here In Washington, where the matter of
rapid transit, especially by electric motors
Is receiving general attention.
There was a very pleasant feature of the
morning session. Yesterday afternoon the
ladies'. who are here with the members of
the association during their convention were
given complimentary drive around the
city. This morning the convention, shortly
after 1t was called to ORDER was presented
with q magnificent basket Of roses. on
which was the following legend: 1.-The ladies
accompanying the n. f. L. A. as guests of
the seventeenth convention of the body
with some great dividends nee diffidence,
expressed by President Armstrong in his
opening address-ask your acceptance of
this expression Of their appreciation of
your courtesy extended to them in a never
to-be-forgotten national drive through the
city of Washington.
"Tennyson has told us that men must
work. and women must weep We would
modestly suggest that Tennyson had the
misfortune not to be acquainted with the
ladies of this association who could have
assured him that Men will work. but never
let women weep at least while guests of
the N. Z. L. A. Sincerely yours
The wives, daughters and sweethearts of
the n. E. l.. A"
The gift was received in a neat and ap-
propriate speech by President Armstrong
and then the convention continued its reg,
uiar business.
r. Mr.. Wallis Paper.
The first paper Of the morning was read
by Mr.. John H. Vail, the well-known New
York electrical expert and a member of
the American Society Of Mechanical En-
gineers and of the American Institute of
Electrical Engineers. Mr.. Vail is thorough
ly familiar in a practical way with under
ole nfrt
accurate knowledge of the various systems
of electrical distribution. His paper was
on the subject, THE Importance of Com
plete Metallic Circuits for Electric Rail-
ways" The paper was of more direct in
terest to railroad people but it contain ed
many points of value more or less directly
to the electric light men.
Trolley Systems.
Mr.. Vail began his paper by a reference
to the fact that in the early days of cleo
trio railway building there were two theor-
les usually followed. One was the double
overhead trolley system, affording a COM
plete metallic circuit for the outgoing and
return Of all the electric current required
to move the motor cars, and the other be-
ing the single trolley system. using the
track and earth as a common conductor
for one side Of the circuit and the trolley
wire and parallel mains for the opposite
side.
The double trolley system was found i'm
practicable Of operation In many of its
details. and the single trolley. because
Of Its simplicity and convenience, has made
rapid advances in public favor. The single
trolley system has depended largely upon
the earth and buried pipe systems for COM
pleting the circuit.
In the early days OF electric railway con-
struction 1t was assumed by experts that
the earth and the buried pipe systems
would, when combined form an ample re-
turn for the electric current. At that age
of ha orf M III NM 70
the immense quantities OF current that
would require to be carried, and therefore
did not foresee that these currents when
disseminated would produce the serious
results that have been caused by electro
lytic action on systems of pipes buried in
the earth and owned by other companies.
Frequent tests prove that the earth itself
cannot afford the free path for the cur
rent that was anticipated. Earth conduc-
tivity has been overestmated.
Destructive System.
Iron and lead pipes, being better con-
ductors than earth, must of necessity carry
the current, II no superior path is Offered
by the method Of construction. The natu-
raj moisture OF the earth hastens the de-
structive electrolytic action of the current
on these pipes. In some soils electrolyss
is more rapid than in others. The rapdity
of action depends upon the chemical con-
stituents of the soil. 1t has been found
that Illuminating gas leakage hastens cleo
trolytic action.
After briefly reviewing the practice of
the past few years in relying upon the sup
posed ability of the earth to carry the
enormous quantities of current required. Mr..
Vail went on to consider the resultant eff
fects. In the course OF his paper he said:
"In cities provided with electric railways
destructive electrolytic corrosion is now
acting upon gas and water pipes. and will
inevitably produce serious impairment of
all such underground pipe systems within
hvfAR Tod laG0 1nf INC ara
taken to prevent further damage. Within
the past year strong evidence OF damaging
electrolytic action has been produced.
Some Examples.
"Simply for the sake of fixing the evil
dence on your memory, will mention only
seven Instances Of electrolytic action of
railway currents on gas and water pipes in
different cities.
"A section Of iron water pipe shows COM
plete perforation, caused in four weeks
time. The lead covering Of telephone ca
bles also show serious damage. A large
number Of additional items will be found
in the report to board Of electric subways
for 1893
"a plumber in q city in Pennsylvania
was repairing a water pipe in a house,
and on breaking joint, an electric arc
formed across the separating ends of the
pipe. This house was not In the direct path
Of the railway circuit.
Investigation followed. proving beyond
question the insufficient electric conductiv-
ity Of the track system; also that the earth
did not afford a good return though the
tracks were well grounded. 1t was found
that the railway current was travelling all
pipe systems in its effort to complete the
circuit to the dynamos in the power sta
ton.
Actual tests were here made by an ex-
pert, using standard instruments. From
135 readings of ampere meter it was found
that the feed water pipes leading in the sta
ton carried an average current Of ninety
three amperes.
Further careful test proved that with
twenty-three cars in operation on the sys-
tenn 40 per cent of the total current was
carried on the underground pipe systems
December 10. $685. a fire occurred in the
basement of James Sutherland's house
After being extinguished investigation
showed that the current of the electric rail-
way system had been carried along the
iron water pipe, and that probably by vi
bration causing the pipe to come in con-
tact an arc formed between the water pipe
and gas pipe, burning a hole through the
gas pipe, and thus set fire to the gas. The
house was saved by prompt action
TESTS show the electric railway current
present on the water pipes. In the gen.
Grating station the fireman gets a shock
when he opens the furnace doors of his
boiler with the bare hand.
"A test recently made by an expert en-
gineer developed the fact Of loss of "a per
cent on the system, and a difference of
twenty-five volts potential between parallel
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