able to fire through it at the rate of 1000 shots a minute with the same certainty as if it were not there, because the automatic gun which he is working is so controlled through the vibration of a column of liquid that it fires only during the period when the shot can pass clear of the revolving propeller blades although that interval of time must be less than the fiftieth of a second. These are but specimens of what Science can do in special cases. But I have preferred to dwell on what may seem to be less sensational matter because it is not these minor though brilliant inventions which have made the war what it has been. We can imagine them absent and yet the war would have been in essence unchanged—we could not eliminate the internal combustion engine, the secondary battery, wireless telegraphy and the improvements in explosives without going back to a war substantially the same as it would have been in 1870. But as an example of the yeoman service that Science is prepared to render in out-of-the-way lines when called upon
