'To place the insect within an induction coil, so as to disturb any magnetic or diamagnetic sensibility which it seems just possible that they may possess.' To treat an insect as you would a magnetic needle and to subject it to the current from an induction coil in order to disturb its magnetism or diamagnetism appeared to me, I must confess, a curious notion, worthy of an imagination in the last ditch. I have but little confidence in our physics, when they pretend to explain life; nevertheless, my respect for the great man would have made me resort to the induction-coils, if I had possessed the necessary apparatus. But my village boasts no scientific resources: if I want an electric spark, I am reduced to rubbing a sheet of paper on my knees. My physics cupboard contains a magnet; and that is about all. When this penury was realised, another method was suggested, simpler than the first and more certain in its results, as Darwin himself considered: 'To make a very thin needle into a magnet; then breaking it into very short pieces, which would still be magnetic, and fastening one of these pieces with some cement on the thorax of the insects to be experimented on. I believe that such a little magnet, from its close proximity to the nervous system of the insect, would affect it more than would the terrestrial currents.' There is still the same idea of turning the insect into a sort of bar magnet. The terrestrial currents guide it when returning to the nest. It becomes a living compass which, withdrawn from the action of the earth by the proximity of a loadstone, loses its sense of direction. With a tiny magnet fastened on its thorax, parallel with the nervous system and more powerful than the terrestrial magnetism by reason of its comparative nearness, the insect will lose its bearings. Naturally, in setting down these lines, I take shelter behind the mighty reputation of the learned begetter of the idea. It would not be accepted as serious coming from a humble person like myself. Obscurity cannot afford these audacious theories. The experiment seems easy; it is not beyond the means at my disposal. Let us attempt it. I magnetise a very fine needle by rubbing it with my bar magnet; I retain only the slenderest part, the point, some five or six millimetres long. (.2 to.23 inch.--Translator's Note.) This broken piece is a perfect magnet: it attracts and repels another magnetised needle hanging from a thread. I am a little puzzled as to the best way to fasten it on the insect's thorax. My assistant of the moment, the pharmaceutical student, requisitions all the adhesives in his laboratory. The best is a sort of cerecloth which he prepares specially with a very fine material. It possesses the advantage that it can be softened at the bowl of one's pipe when the time comes to operate out of doors.