228 Short Papers and Notes. 
one case a butterfly fell to the ground before its opening wings had 
dried, and a soldier-ant tried to rescue it. He carried it back to 
the tree with the utmost care, and made several attempts to assist 
the butterfly to hold on again, but finding his efforts unavailing he 
left the cripple to recover himself. On his return, seeing no 
improvement, he appeared to lose all patience, and, rushing in, bit 
off both wings and carried the body into the nest. But high- 
handed proceedings of this kind are very unusual. It is said to 
be a curious sight to watch the fragile and delicate butterflies 
wandering about, all feeble and helpless, among the busy crowd 
of coarse black ants, and rubbing shoulders in perfect safety with 
the ordinary fierce, big-headed soldiers. A larva of another 
species thrown down among them as an experiment was imme- 
diately set upon and torn to pieces by the ants. 
Wlater=Gas. 
Recently, under the auspices of the Society of Chemical 
Industry, Mr. Alfred Wilson lectured at the Mason College, Bir- 
mingham, on ‘ Water-Gas for Heating and Illuminating.” Mr. 
Wilson described generators for the manufacture of water-gas, 
such as are now in use in some European cities, principally in 
Germany and Austria, for the melting of steel, and also for illu- 
minating purposes. The fuel employed for making this kind of 
gas is coke, of the kind which remains at gas-works after the 
illuminating gas of every-day use has been abstracted from the 
coal. The method of producing gas is as follows :—A cupola- 
shaped furnace is employed, in which the coke is raised to an 
incandescent heat by means of a blast of air. When it reaches 
that temperature, steam is passed through it and suffers disin- 
tegration, with the result that an inflammable mixture of hydrogen 
and carbonic-oxide is obtained. The mixture is then passed 
through a water-scrubber in the ordinary manner, and thence goes 
to the gas-holder. It is burnt as an illuminant with the aid of a 
new incandescent burner, known as the Fahnejelm, having a 
magnesia cone, and is so brilliant that a No. 3 Bray burner gives 
a light equal to that of twenty sperm candles of standard make. 
Its cost is understood to be about sixpence per 1,000 cubic feet.— 
Photographic News. 
The Wearest Star. 
The distances of the stars are ascertained in the same manner 
as those of the sun and planets—that is, by parallax. Instead, 
however, of taking two stations at the different parts of the earth’s 
surface, and laying down a base line between them, we take the 
