WONDERS OF PHOTOGRAPHY. 609 
At the government dockyards, when experiments were being made with 
torpedoes, the aid of photography was invoked. Rapid views of the torpedo 
explosions were taken, showing the upraised fountain of water and registering 
the exact height to which it was thrown. Views of rocks, buildings, or old ves- 
sels being blown up by dynamite, show the fragments as it were suspended in 
the air, the artist being able to expose his plate precisely at the moment required. 
At Shoeburyness a regular staff of artists was employed in photographing the 
effects of artillery experiments against iron and steel armor-plates. Again, in 
many of our prisons, portaits of all prisoners of a certain class are regularly taken, 
and, if necessary, produced by hundreds and distributed throughout the country. 
The detective camera, a small instrument which can be held in one hand, may 
be of incalculable use in obtaining portraits of any suspected persons in the 
streets, and in this way identification of criminals might be much facilitated. 
Recently, quite a novel use has been found for photography. The Chinese, 
who in their own way are an extremely enterprising race, are troubled with a 
language which is a stumbhng-block not only to foreigners but even to them- 
selves. The number of signs or letters is so great that an ordinary printer's com- 
positor would be perfectly bewildered; his type case would be a wilderness of 
boxes ; in fact, to print a newspaper in Chinese would be nearly impossible. An 
enterprising publisher, however, has recently hit on the plan of having one copy 
of a newspaper written out and then multiplying the copies by photography, 
using one of the many mechanical photographic printing processes. 
But to enumerate all the wonders of photography is impossible : one more 
must suffice. It has been found practicable, under certain conditions, to photo- 
graph invisible objects. It is well known that in the spectrum of white light there 
are rays which are quite invisible to the human eye : we refer to the chemical 
rays beyond the violet end and the ultra-red or heat rays. But the eye is far 
from perfect, and the rays that it cannot see can still be rendered perceptible by 
other means; for instance, bisulphate of quinine placed in the invisible chemical 
rays is at once rendered fluorescent. In a similar way, Captain Abney finds 
that the bromide of silver used by the photographer can be so modified as to 
become sensitive to the invisible ultra-red rays; and we are told by Mr. Proctor 
that he has " taken the photograph of a kettle of boiling water /« //^ii? ^^;^^ by 
means of its own radiation." In some of the photographs of the great nebula of 
Orion are clearly seen traces of certain dark bodies in space, while they are 
invisible through the telescope ; and it is at any rate not within the region of ab- 
surdity to suggest that photography may some day reveal to us the existence of 
worlds enveloped in perpetual darkness — suns, perhaps once as bright as ours, 
but whose light has been dimmed by the lapse of millions of years; stars and 
systems which are no longer visible, but which still move in space in accordance 
with the unfailing laws of the universe. — Cornhill Magazine. 
