The sun. [volume] (New York [N.Y.]) 1833-1916, 1879-01-29
THE LAMPS or THE FUTURE
An Electricity Man Replies 90 Some of the
CrItIcisms nr the Chs Mcn.

An Electricity Man Replies 10 Some of the
Criticisms or the Gus Men.
To THE EDITOR OF THE SUN-Sir! In
reading the article on electric lighting in THE
Sun ofto-day, it occurred to mo that it would he
Just as well Tor all concerned. and Il most scnst-
bic proceeding. II the parties who take Opposite
sides upon this question would ccnfne thcm-
selves to facis and cease cXaggorating.
In his statement concerning the cost OF an
electric lighting plant" Mr.. Wakemnn IL
doubtless sincere. but shall show that he IL
entirely mistaken; for. unlike gas works CEN
trail stations for tho distribution OF electricity
which include merely steam engines and
dynamo electric machines. need never be To-
Gated Mt n greater distance than one-haf mile
from tho most remote limp to be operated. and
oven then n single station would sunlce to sup
ply on area such ms would bc contained in
circle ono milo in diameter the averlgn dis
tancr OF tho lamps from the source Of supply
being. in properly selected nrigh'orhpod.
say unc-qunrtcr mile. MS against On nverhH" 81
urnrly one mile according to Mr.. WHkDmun.
The cost Of tho plant Tor lighting the city Of
Berlin estimated NJ 500 050 900. is therefore, by
this item alono reduced ilteon iNtrenths. or 70
say A.O0O!001. In conccding that the powerful
engines. DC. nre perfectly praciicaDle, Mr.
Wakcman comedies everything. The electric
cinns cau take care VI the rest.
=. Although somewhat Interested IN ciectrlc
lighting. / nm personally Tar from believing
that its accomplishment VIII IN ny ond nint,,-
rally injure the gas plants. IN order to absorb
the cream Il the business ot public and privnte
illumination. ii does not follow That electro
mnins need be- run into tenement house and
poor paving districts. Nor can electricity ever
supplnnt cns for heating purposes.
The distribution OF the electric current is by
no means u difficult matter. IL is not only the
simplest of all things. hut II is don" every day
IN the operation Of telcgrnphic circuits. let us
Western WcsS Tn' Union 6uiidns, for example. Con.
nectrd with il there are three. or 1t mny be ten
different lines of telegraph, md IN each of those
lines Of telegraph there are from ter to tNrnty
instruments NJ IA many remote stntions. sup
pose there ara ten wires. ana ou ench ten in
sfrumcnte. Each aud every one uf these In
etruments Ia operated 10y the current from tho
one generator. In place ot these luu telegraph
Instruments. substitute 100 electric inmp-. nm,
II there If u sufficient supply OF electricity.
would like to ask II this Is not distribution u
electricity md division 90 the electric liEht :
Aud II the conductors be- sufficiently large, and
the supply sufficiently great. what Is the init
10 the number ~ lamIs thnt can be- run by II
single generntor? Ceftainly It is not one. nor
one hundred. nor one million.
The question often rniscd ~ 20 the size OF the
electric ccnduits required in lighting a city r.
easily met. In no rgse will the amount OF metal
rrauirci Tor aiactric mains npp-oarh the amount
of metal required for ga- mains; and ] refer
now to iron MAINS Tor iron may hr uscu ior
i. ference ns to iron md copper conductors
hong TINT the former should be- about 2 times
tho diameter OF the latter. suppose that two
copper mains are laid Under the streets Tor n
distance ot one mile from tho central station.
ma tnnt thos" two mains nre To- carry the cur
rent for loo 600 electric lamps. These mains do
not run into houses. the hous" connections h,-
! ing from smaller copper Wir"e running across
| from main 10 main. and the wires travrrsnR n
| huuar seldom n"ed exceed b in n in diameter.
| What should he the size ofthe two copper mains 2
! Not over one inch In diameter. tn" rrsisinnrc
| OF these mains. the two fOrmnga conductor two
miles in length. would not exceed = of an ohm.
| From thee" mains run 100 branches. each con-
tanning 600 lamps, aud. the res lstaur" OF each
| lamp being .jOt mn ohm. the Resistance" 81 cn
branch would be 500 ohms; but thcr" being loo
| branches, the Joint Resistance 81 III" circuit
would be, say. ohms. ~ IN" mans ar" round
! wires OF only inch in diameter they may heat
30 rs To- Increase their rrsstnncc; but fiat. the
! heat is RAPIDLY dssipatcd. md the flnttrr they
nre the more rapidly Is the heat dissipat"d
hence ma tho mass Of an iron conductor o. equal
! condutiyitv II or times the innss OF copper
! conductor II VIZ should replace the inch oup-
per wire 10y an iron conductor. the Inter would
| have TO be about ~ inches IN diameter, aud
! the iron conductor. hattrnnd ont. would present
| greater cooling surface h"ncc,iron mains would
/ be- better than copper mains. and would rcnai n
cool under extremely powerful currents. The
| current required being Oi comparatively low
| tension. such insulation as is necessary on tele-
| graph lines IS AvOidpi.
! Tho Internal resistance Of the generators re-
| quirrd 10 supply thcs" two-inile mains for
! 100 600 lights, say twenty-five in number
/ coupled together IN multiple. would be each say
| olltns. ana their Joint rrhisiuncr would Ore hui
! - OF nm ohm. Allowing Tor proper nincins NJ
the branches across the mains. the Resistance =
Of the various parts Of the Circuit would BE-. IN
| the generators. 2 of an ohm IN the mains and
! lamps, 81 ohms, Tho total force generated
would be- expended, first in heating the gen
! ernting machines lO-3G5 ot the current. or sHy
! l-26: in heating the mains, los; in giving
| light. 5o-59 NJ the whole current. where IL l.
| needed, Thus It is clear that the proportion %
| heat in the mains would Ice 80 slight TINT their
! conductivity would, remain unchanged; very
! large mains nrs not necessary to carry very
! powerful currents. n thnt is necessary being
| that the mains shall be OF low resistance. and
! not heated 10 any considerable extent
1t can hardly be considered settled fact b..
| cause the electric Light for houses IS not pu'
! into general operation within three months
subsequent to It's discovery. thHt the project has
/ been abandoned or IL chimorloR. UVdro-car
! bon gas was known and used quite u little Will,
| before New York got II. and an accounts ~ q
show that when 1t did get IL. il ~, very poor
| quality. II there Is nothing in N" electric llsh
| of this or that inventor, no amount Of adVer
Using will make IL q success: and II IL Is su.
| cess. AMI is shown TO be a success no arnoun
Of argument will prove that 1t is uutso.
W. l.. SAWYER.
"a WALLER STREET. NEW YoE1. Jan. q.