Lamp, Holophote.
A lamp designed for use alone upon its own circuit. These have the
regulating mechanism in series with the carbon and arc, so that the
whole current goes through both. (See Lamp, Arc.)
Synonym--Monophote Lamp.
Lamp-hour.
A unit of commercial supply of electric energy; the volt-coulombs
required to maintain an electric lamp for one hour. A sixteen-candle
power incandescent lamp is practically the lamp alluded to, and requires
about half an ampere current at 110 volts, making a lamp-hour equal to
about 198,000 volt-coulombs.
[Transcriber's note: 0.55 KW hours.]
Lamp, Incandescent.
An electric lamp in which the light is produced by heating to whiteness
a refractory conductor by the passage of a current of electricity. It is
distinguished from an arc lamp (which etymologically is also an
incandescent lamp) by the absence of any break in the continuity of its
refractory conductor. Many different forms and methods of construction
have been tried, but now all have settled into approximately the same
type.
The incandescent lamp consists of a small glass bulb, called the
lamp-chamber, which is exhausted of air and hermetically sealed. It
contains a filament of carbon, bent into a loop of more or less simple
shape. This shape prevents any tensile strain upon the loop and also
approximates to the outline of a regular flame.
Fig. 212. INCANDESCENT ELECTRIC LAMP.