Page:Popular Science Monthly Volume 50.djvu/154

142 investigation which are of general interest outside of the bounds of their several specialties, and summaries; comprehensive reviews of the more important events in the progress of investigation, weeding out what is temporary or subsidiary, and presenting only that which is of lasting value and a literary record.

, of Barmen, is authority for the following statements regarding mineral wool, or silicate cotton, as it is sometimes called. The wool appears on the market in a variety of colors, and is coming to be used very extensively as a non-conductor of heat and also as a protection against fire. It is made by blowing molten rock into a fibrous woolly state by means of a jet of steam. The furnace slag or the rock, as the case may be, is melted in a large cupola, and as it trickles out at the taphole in a somewhat sluggish stream it meets a high-pressure steam jet which blows it into a woolly, fibrous condition, in which state it settles in fleecy clouds on the floor, the heavier wool coming down first, while the lighter portions are blown farther along by the force of the steam. The material thus naturally grades itself.

an inquiry whether fishes have a sense of hearing, Herr A. Kreidt experimented upon goldfish—normal, fish poisoned with strychnine, and fish deprived of their labyrinths. Sounds were made by sonorous rods plunged in the aquarium, to which tuning forks or bows were applied out of the water. Whistling and the ringing of bells outside of the water produced no impression on either of the three classes experimented upon. But all responded whenever the apparatus within the aquarium was struck with the production of an audible sound. The conclusion was drawn that fish do not hear as in ordinary hearing with the ears, but that they are sensitive to sonorous waves which they can perceive through some skin-sense.

, in introducing a bill in the English House of Commons, which was intended to ameliorate the widespread agricultural depression, gave some striking facts regarding the present unjust methods of taxing land. One instance, of two men living side by side, each of whom started in life with $100,000. A invested his money in various securities, and now has an income of $2,800 a year. He lives in a house rated at $200 a year, and his rates come to about $22. B invested his capital in a farm, for which be paid $75,000, and afterward put $25,000 in as tenants' capital. His farm is rated at about $2,585, and his rates amount to about $335. Another striking case was that of a factory employing 2,000 hands, rated for local purposes at $2,000. A farm of 200 acres in the same parish is assessed at $2,300, and pays more to the local rates than the factory. Another case cited was that of a farm of 265 acres in Essex, where the rent was only about $76 and the rates $90.

International Atlas of Clouds has been published under the direction of a committee consisting of M. Hildebransson, of Upsala; Riggenbach, of Basle; and Tesserenc de Bort, of Paris. It contains fourteen plates, each including two or three figures, the several classes of clouds in the classification adopted being represented by from one figure for the "fracto-nimbus" to ten for the cumulus, while some transitional forms are also delineated. The figures have been selected from more than three hundred representations of clouds from all quarters of the earth. The plates have been approved by eminent meteorologists, and their accuracy is guaranteed. In the text are given the definitions and official instructions adopted by the International Meteorological Committee at its meeting in Upsala in 1894.

is proposed to explore the island or rock of Rockall, which is situated in the open Atlantic, in 57° 36′ north latitude, about two hundred miles west of the Hebrides, with no other land nearer. It is about two hundred and thirty feet in circumference at the base and sixty feet at the top, and looks at a distance like a ship under sail, being whitened by the guano that has been deposited upon it. It appears to be the emerged point of an extensive mountainous submarine table land, stretching from the southwest to the northeast, and giving rise to a number of dangerous rocks and reefs in the neighborhood. It offers advantages of great promise as a meteorological station, situated as it is in the zone of the most extensive area of cyclones in the