With a view to ascertaining whether or not matter which has hitherto been known as non-living could be proved so under the test of the galvanometer, the Professor attached the instrument to bars of different metals, with startling contrary results. The Professor found that all metals show visible signs of sensitiveness when twisted or tapped. The greater the irritation the greater the visible signs of sensitiveness; even every single peculiarity in the irritability of animal matter is exactly reproduced in the case of metal. As, for instance, when the sensitiveness of a muscle or a nerve of an animal wears off after a time, under repeated irritation, it begins to show signs of fatigue, the deflection of the needle of the galvanometer becoming more and more feeble; the Professor found that metals would betray exactly the same signs of fatigue under repeated irritation. Again, after a short rest, the signs of fatigue were found to disappear in animal muscle and in metal alike, their sensitiveness being fully restored. This last fact is known to many of us who constantly use a razor and find it losing its keen edge and growing duller and duller, despite vigorous stropping, and spontaneously recovering its original keenness by being laid aside for a few days. Professor Bose's process of registering the deflections of the needle of the galvanometer is this: By a mechanical device the point of the needle is photographed on paper, which is moved along at a constant rate, the needle's point tracing out a series of zig-zag lines on the paper, when the needle is oscillated by an electric current. The width of the zig-zags corresponds to the amount of the deflection of the needle, therefore the strength of the electric current. If there be no current, and consequently no deflection of the needle, its point will remain stationary and merely trace a straight line on the moving paper. This book of Prof. Bose's, "Response in the Living and the Non-Living," is full of still more wonderful revelations. He has found and shown, to the satisfaction of European scientists through experiments, that metals do not only go to sleep, but can be poisoned and killed like human beings and animals. Like an unused animal muscle showing signs of sluggishness and appearing to be in a kind of torpor, then gradually seeming to waken up under irritation, and finally returning to full activity, Professor Bose proves that metals behave in exactly the same way and process of gradation. He also proves that the effects of extreme cold and extreme heat produce exactly similar conditions in both animals and metals.