Some artillery officers in Switzerland have been putting their snow-clad mountain flanks to a curious experimental use, for they have been employing one of them as a gigantic target for their missiles. A space on this snow-covered ground measuring two hundred and thirty feet by ninety-eight feet—which would represent the area occupied by a battalion of infantry in double column—was carefully marked out, its centre being occupied by flags. At a distance of about a mile, the artillery opened fire upon this mapped-out space until they had expended three hundred shots. The ground was then examined; and the pits in the snow when counted showed that seventy-eight per cent. of the shots had entered the inclosure. Had a veritable battalion occupied the ground, there would have been few, if any survivors. In another experiment, snow was employed as a means of defence against artillery. A wall sixteen and a half feet long, and five feet high, was built of snow having various thicknesses, but backed by half-inch wooden planking. This wall was divided into three sections, having a thickness respectively of four and a half feet, three feet, and twenty inches. Against the thickest section, twelve shots were fired from various distances; but in no case was penetration effected. In the three-foot section, shots pierced the snow as far as the woodwork, where they were stopped. In the twenty-inch section, all the shots fired went completely through the wall. It would seem from these experiments that snow, when available, can be made a valuable means of defence. But, unfortunately, in the published account of the experiments, the calibre of the guns employed is not given; we should, however, assume them to be field-artillery of a very light type. A new use for the ubiquitous dynamo-electric machine is reported from Saxony, and one which seems to fulfil a most useful purpose—namely, the ventilation of mines. At the Carola pits, Messrs Siemens and Halske, the German electricians, have inaugurated this new system. At the pit bank, a dynamo is stationed, which is coupled up by shafting with the engine. By means of copper conductors, this machine is connected with another dynamo, two thousand five hundred feet away in the depths of the mine. This latter is connected with a powerful centrifugal fan. The cost of working these combined machines is six shillings and threepence per day, which means threepence for every million cubic feet of air delivered.