734 Meeting of the British Association. [Oct., 



said that these phenomena, which he characterized as entirely novel, 

 could be obtained with any insulated battery. 



A paper " On Spectacles for Divers, and on the Vision of Amphi- 

 bious Animals," was then read by Captain Galton. The author said 

 those who had surmounted the usual repugnance of beginners to keep 

 their eyes open under water, found, if they did so, that nothing was to 

 be seen with distinctness — everything they could see at all, was seen 

 through a haze ; so that if the hands were held out to a distance of 

 eight inches before the face, it would be impossible to discover the 

 space between the fingers, even if they were spread out as widely as 

 possible. If he looked through a tube into a vessel of water perfectly 

 still, he saw all objects at its bottom with perfect distinctness, only a 

 little out of their position through the effects of refraction. But 

 upon lowering his head he found that the instant his eye touched the 

 water all distinctness vanished — the convex surface of the eye-ball 

 had indented the plane surface of the water, and turned the tube into 

 a convex lens. If they . desired to counteract this they must use a 

 convex lens of such power that its effect should be exactly opposite to 

 that of the concave water lens. A lens to answer that purpose he had 

 made and now produced. Furnished with spectacles on such a prin- 

 ciple, they might expect to see as well under water as on dry land. 

 Men going down in diving bells did not require such aid ; through 

 the plate-glass inserted in the diving dress, they could see clearly 

 when in the water. He designed his contrivance to be useful to the 

 pearl-diver, .to the sailor requiring to examine a ship's bottom, to men 

 seeking in the water anything they may have lost there, and to 

 bathers generally, to whom he promised that the possession of these 

 spectacles would add much to their enjoyment. They would find 

 they had acquired a new power. With respect to the amphibiae, he 

 thought their power of accommodating the vision was wholly inex- 

 plicable by any theory he had heard promulgated. The hippopotamus, 

 otters, water-rats, and diving birds of various descriptions, apparently 

 saw as well in water as on land. The cornea of the seal appeared to 

 be very flat, but it was far otherwise with the rest of the amphibia?. 



Captain Selwyn then read a paper, " On some New Arrangement of 

 the Poles in Magnets," in which he described an experiment he had 

 made on this subject. A steel bar having been prepared and hardened 

 as usual, was magnetized by any ordinary means — either by touch or 

 an electric current. Then, either at the centre or any other point 

 of the bar, where it was desired, the temper was taken out of the 

 bar by a rod of heated metal or by a blow-pipe, when it was found 

 that this operation separating the bar into two magnets, the ends 

 of the bar still remained respectively north and south. 



The last paper in the Section this day was one by Mr. Harrison, 

 " On the Heat attained by the Moon under Solar Eadiation." After 

 referring to various theories on the subject, Mr. Harrison expressed 

 his opinion that a small modicum of heat having been detected in the 

 course of researches into the question made by Professor Smythe at 

 Teneriffe, justified the assumption that the moon's radiant heat was 



