20S 
crystals, instead of its sides merely. This has a very beau¬ 
tiful effect at night. 
If the lamp is intended to light a dining hall or billiard 
room, it will be necessary to omit the lower half of the 
screen and substitute gauze or white crape, with a band five 
or six inches broad, and of the same diameter as the band 
of gilded copper which supports the lamp. This band of 
crape may be ornamented externally with Bohemian crys¬ 
tals, in festoons or pendants, suspended from the lower sur¬ 
face of the copper band. 
A lamp with three wicks is perfectly sufficient to light a 
dining room, twenty-four feet in length and twenty in 
breadth, but in order to light a billiard room, one with four 
wicks will be required, and it is also necessary that it should 
be suspended at a convenient height over the middle of the 
billiard table. No inconvenience can result from this, since 
the lamp does not spill a single drop of oil. In this man¬ 
ner many billiard rooms in Paris are at present lighted. 
The reason of the superiority of this mode over the one 
formerly in use may be easily explained. When a billiard 
room is lighted by a number of lamps, placed in different 
parts, every ball reflects the light of three or four at once 
and presents to the eye as many luminous points on its sur¬ 
face, together with the same number of shades, intermixed. 
This renders the object very confused and indistinct. But 
when all the Jlames are united, the source of the light which 
illuminates the room and the objects contained in it,is unique , 
and every ball presents to the eye a single luminous point, 
and a single shade, both well marked, and seen distinctly and 
with ease. To this may be added, that when a hall is light¬ 
ed with several lamps, distributed in various parts, the eye 
is constantly fatigued by the dazzling glare of one or other 
of them; but with a lamp enclosed in a large screen, or 
half-screen and band, the flame is never disagreeable to the 
eye. 
There is another kind of lamp, with a single wick, con- 
