The daily morning journal and courier. [volume] (New Haven, Conn.) 1894-1907, 1905-08-03
STREET LIGHTING.

Quality and prices aside, gas and
electricity compete on more nearly
equal terms in distributed street light
ing than in most, other lines of service.
By distributed street lighting is meant
that which must be done with a COM
paratiVely large number of rather low
candle power lamps, as where only
small sum can be expended a mile of
|street, or where shade trees are so
thick that good results can be obtain
ed only with lamps close together.
These conditions make the use of arc
lamps impracticabIe, and the compari-
son comes between gas ana electric in
candescel1t lamps.
The i1candescent gas mantel has
raised gas street lamps to a position of
Importance that the open bats wing
flame long since lost. This return of
prestige to the gas lamps Is due to the
fact that the incadescent burner in
creases its illuminating power to as
much as five times that Of an open
flame. For the bats wing burner a
fair result may be taken as fifteen
candle power, with a consumption of
five cubic feet Of gas an hour, or three
candle power hours per cubic foot. In
the incandescent burner under good
conditions it is practicable to get as
much as fifteen candle power hours
cubic foot Of gas consumed an hour.
In street lighting, unlike interior IL
Illumination, the heating effects, Vita
| ton of the air, and the fire risk Of gas
lamps do not weigh heavily against
them, and the main factors to be con-
sidered are location. candle power and
costs. Gas lamps, as ordinarily erect
ed for street lighting, are at serious
disadvantage as compared with, incan-
descent electric lamps of equal candle
power. This disadvantage is due to
the fact that the gas lamp is too near
| the ground; its lantern holder and post
! cast a large shadow, and 1t lacks an
| effective reflector above it. In con-
trast with all this, the incandescent
electric lamp may easily be, and usual
| ly is, a suitable height above the
ground, has a wide reflector above it
and there are no opaque parts at the
side Of or below the incandescent fila
ment to cast shadows.
! Another disadvantage of the gas com
pared with the electric street lamp, as
ordinarily erected, where there is a
row Of trees on either side of the
street, is that the gas lamp, being
mounted at the top of a straight post
between the trees, throws gigantic
shadows to long distances up and
down the roadway. The electric lamp,
being held out beyond the trees by a
goose neck, throws it's light to lis
lance up and down the roadway, where
| it is most needed. If gas companies
can supply an inverted burner and
mount it at the end Of a long goose
neck, they will materially increase
their power Of competition in distribut-
ed street lighting,
Most important among the factors
that determine the selection of gas or
electric incandescent sweet lamps Is
the cost per candle power of each.
This conclusion is borne out by the
fact that gas street lamps are largely
used in cities of the first and second
class, where gas is cheap, while in
small cities and towns, where gas Is
] hiuIh Ii5uSlS lliGdluSSCSIlL SlSCITIC
stree lamps are much more generally
used. For street lighting ineandes-
cent electric lamps rated at 25 candle
power and consuming about seventy
five watts are very commonly en-
ployed. With equally good location
and mounting for each lamp which is
contrary to the facts as above noted
about two cubic feet of good gas per
hour in the gas lamp will give an il.
Eliminating effect equal to that of the
rs watt incandescent lamp. If the gas
sells at 81 per thousand cubic feet the
operation of this lamp costs or cent
per hour. To equal this cost of operat-
ing energy fordthe rs watt incandes-
cent lamp must be sold at 2.66 cents
per kiIowatt hour Where the price of
gas is 81 per thousand feet, as in
man small places, the equivalent price
of electric energy may be raised to g.
80 cents per kilowatt hour, and a large
amount of ineandescent electric street
street lighting is done at not more
than thiaefgvree~Ele Electrical Review. '>