270 Scientific Intelligence. 
it affords an excellent soup, and passes into a condition, in whic 
cannot be distinguished from fresh meat.—From Le Génie Industriel ; 
in Boerrasn’s polytechnisches Notizblatt, 1860, xv, 1 
- Magnesium as a Source of Light—Prof. A. Scumrrr calls attention 
to the practicability of employing metallic magnesium for purposes of 
illumination, as had already been suggested by Bunsen. From the re- 
r of the last named chemist, it is known that when magnesium is 
ignited it readily takes fire and burns with an exceedingly brilliant flame. 
The intensity of the light thus produced, as determined by Bunsen and 
Roscoe in one of their photo-chemical researches (Pogg. Annalen, eviii, 
261, et seq.) is only some 525 times less than that of the sun. Compar 
ith an ordinary candle, it appeared that a wire of magnesium 0:297 
millimetre [1 mm. =0-0394 inch] in diameter, produced as much light 
in burning as 74 stearine candles, five to the pound. In order to support 
this light during one minute, a piece of wire 0-987 metres long, weighing 
0°1204 gram [1 grm. =15°4325 grains], was required. 
Only 72:2 grams of magnesium, therefore, would be needed, in order 
to maintain during ten hours an amount of light equal to that of 74 
stearine candles, consuming about 10:000 grams “of stearine. 
ecording to Bunsen, magnesium wire is readily obtained, by forcibly 
pressing the metal through a hot steel die by means of a steel piston. 
Bunsen’s arrangement for burning the wire was made, i 
spools of it with rollers moved by clock-work so that the wire should 
unrolled like the ribbon of paper in Morse’s telegraph, the end of the 
wire thus gradually pushed forward, passed into the flame of an ordinary 
alcohol lamp, where it took fire. ‘ 
It is evident that a magnesium lamp of this sort must be rouch simpler 
and more compendious than any of the existing arrangements of the elec- 
trical, or of Drummond's light; for light-houses, &c.: where an intensely 
brilliant illumination is required it can hardly fail to rival either of these. 
Where an extraordinary amount of light is needed, it could readily be 
produced by burning large wires, or several thin ones at the same time. 
Another important consideration is the fact that. the spools of wire, 48 
g by night or in any dark or subterranean locality ; the evenness an 
remarkable tranquillity of the flame, especially commending it for this 
rpose. 
The present high price of magnesium, it is true, must prevent any &* 
tended use of it for technical purposes. For example, Lenoir of Vienna 
by connecting — 
be 
; 
: 
3 
a 
ES 
