which life is made up, nor of the production of living beings, but of the origin of those attributes by which living things are especially characterized, and in which they differ from all other forms of existence.
RECENT wars have had particular interest for the man of science. If we go back some fifteen or twenty years and consider the different wars which have unfortunately occurred since that time, we shall find connected with each one of them certain features which undoubtedly mark progress in the art of killing and wounding. Some argue—and on very good grounds, no doubt—that the more sharp and terrible warfare is made, the more speedily must it come to an end, and hence look with favor upon the means taken every day to render weapons more destructive and the soldier more cunning in his dangerous trade. We do not propose to discuss this argument, nor to enter at all into any comparison between the wars of our forefathers and those of to-day, but at a crisis like the present we need hardly apologize for bringing before our readers some points illustrating the marked influence of science upon modern warfare.
Starting from the close of the Crimean War, the first in which the electric telegraph was employed, we find ample examples of the assistance furnished to the soldier by scientific research. One instance taken from the war of 1858 is especially interesting. The Austrians held Venice at the time, it may be remembered, and, to protect the harbor, torpedoes were laid down. The torpedoes were fired by electricity, and contained gun-cotton, this being the first instance on record of the employment of electric torpedoes and of the newly-invented nitro-compounds. Nor was this all. The torpedo system devised at Venice by the Austrian engineers had yet another point of scientific interest. A camera-obscura was built overlooking the harbor, and upon the white table of this instrument were reflected the waters of Venice. As the torpedoes were sunk one by one a sentinel in the camera noted the place of their disappearance with a pencil, giving each torpedo a consecutive number. A row-boat in the harbor described a circle around the sunken torpedo, indicating the zone of its destructive power, and the sentinel again, with his pencil, made a corresponding ring upon the camera-table. In the end, therefore, while the harbor itself was apparently free from all obstruction, a very effective means of torpedo-defense was established, the key of which was only to be found in the camera-obscura. The sentinel here had wires in connection with every torpedo, and was in a position to fire