Rensselaer Union, Volume 7, Number 48, Rensselaer, Jasper County, 19 August 1875 — MECHANICAL AND SCIENTIFIC. [ARTICLE]

MECHANICAL AND SCIENTIFIC.

—The somewhat novel theory has recently been advanced by M. Meunier that the planet Mars is much older than the earth, because of the rarifleation of its atmospheres and the small extent of its seas. The form of the latter, according to M. Meunier, is exactly that which the terrestrial oceans would assume after partial absorption by the earth’s crust. If, for example, the Atlantic Ocean were absorlied so that only that portion included in the contour made bv the uniform depth of 12,000 feet were left, the shape would be in all respects similar to that of some of the seas recognized in Mars. M. Meunier’s theory will hardly be accepted, we think, in astronomical circles. — N. Y. Sun. —M. Schering states that glycerine may be burned in any lamp so long as the flame is kept on a level with the liquid. The latter, on account of its consistence, will not ascend an elevated wick. As the flame, like that of alcohol, is almost colorless, and as the material Is especially adapted for absorbing a large proportion of saline substances, M. Schering has recently made experiments in coloring the flame with various bodies and with satisfactory results. By introducing substances rich in carlion it appears that the flame may be rendered suitable for illuminating purposes. The low priceofglycerine and its property of not volatilizing at high temperatures add to its advantages in this direction. . —The union of Europe and Africa, by means of a tunnel under the Straits of Gibraltar, is one of the great engineering schemes at present contemplated. This tunnel, as projected, is to be a right line, extending between Tarifa and Algesiras, on the Spanish coast, to Ceuta and Tangier, on the Morocco shore, the Submarine portion to be 44,1(10 feet in length, or nearly nine miles. This vast enterprise offers, it is said, more difficulties than the similar Work under the English Channel, altliough the latter will have more than twice the length. The maximum depth of the channel at the point to be traversed is stated to be only-163 feet, while that of the Straits Is 2,621 feet. Supposing the tunnel under Gibraltar to be bored at a distance of 1,000 feet under the bed, its total depth under the sea level would be over 3,600, while the entry and exit galleries would be each three miles in length. —A method of coat ing iron with copper -so as to protect the foriner from tlie action of sea water and the like is described in the Deutsche niust. Zeitung. The iron, it appears, is first cleaned and rendered perfectly bright by means of acid and then immersed in a bath of melted copper, which is maintained at a very high temperature, so that it not only covers the iron becomes incorporated with it. Iron coppered in this way can, it is said, be hammered and rolled without the copper tearing or-peeling off, and specimens left in contact with sea water for a period of nine months have been found unattacked and capable of being hammered and rolled out like new metal. Iron plates covered with copper in this way are claimed to possess two important advantages over pure copper plates, namely: they cost less and are harder and stronger. There is also a great advantage in using coppered iron wire for telegraph lines instead of galvanized iron.