tas ae 
March 9, 1882] 
NATURE 
447 
In addition to these lamps Mr. Edison also exhibits | out of sight. The interior of the frame is, however, 
some very handsome sconce mirrors supplied by Messrs. 
Verity and Sons. One of these is a novelty in its way, 
whitened, and reflects the light out through narrow panes 
of clouded glass which flank the central mirror, and the 
since the bulb lighting it is inside the frame, and therefore | face of the spectator thus illuminated can be seen in the 
Fic. 1. 
mirror. This is another effect which could not be pro- 
duced by gas. The other sconces are lit by naked bulbs, 
supported by in front of the mirrors, curving brass 
brackets in which the ruling idea of foliage and flower or 
fruit is elegantly worked out. 
Fic. 3. 
In the Concert Room, opposite the Entertainment Court; 
there are some 280 lamps, about forty of which are termed 
“‘half-lights,” that is, giving 8 candle-power, or a light one- 
half of the full 16 candle-lights. Of these 120 are hung in 
Fro. 2. 
festoons between the pillars of the galleries, the rest being 
suspended in sets of four under the galleries, or fixed 
within a large crystal lustre suspended from the roof, and 
looking like a nest of diamonds. In the Entertainment 
Court and Concert Room together there are nearly 500 
lights, and the stalls in the wide avenue leading to the 
railway station, have yet to be lighted. In all there will 
be about 700 lamps required when the exhibit is com- 
plete. To drive the 500 lamps now going there are eight 
dynamo-electric machines at work, and four more are 
being got ready for the remaining 200 lights. Three 
Robey engines of 25 horse-power nominal are planted to 
work these machines, one engine to every four machines. 
It is usual to allow ten lamps to each horse-power, but 
what the actual power consumed may be is difficult to state, 
The lamp itself consists of a strong bulb of glass about 
the shape and size of a large Jargonelle pear, say 44 
inches long by 24 inches in diameter at the thickest part. 
From the narrow end a tube of glass projects nearly half- 
way into the bulb, and contains ,the ends of the copper 
