Rensselaer Union, Volume 8, Number 19, Rensselaer, Jasper County, 27 January 1876 — MECHANICAL AND SCIENTIFIC. [ARTICLE]

MECHANICAL AND SCIENTIFIC.

—Mi. Hossock, an English horticulturist, grafted the tomato on a common potato —both plants being species of Solanum. The result was curious in this, that the potato roots under these circumstances refused to form tubers. —A. piece of carbonized rough basket or wattle work has been discovered in the interglacial coal-bed at Wetziken, Switzerland, giving what seems to be clear evidence of the existence of man during one of the warm intervals of the glacial epoch. —Magnets prepared by compressing iron filings in tubes have been exhibited to the French Academy by M. Jamin. When soft iron tilings are forcibly compressed by hydraulic pressure they acquire a coercive power equal to that of steel. —According to Mr. John Young, the sandstone bottoms of iron furnaces assume, from the long-continued action of heat, a distinctly columnar form, the old lines of stratification being obliterated, thus showing that heat, as well as electricity and mechanical force, was an agent in the production of the columnar form of rocks.

—The new aeronautical invention, the parakite, has been exhibited to the public at the Alexandra Park; but,.as it was represented only by a small specimen, the results of the exhibition are not very tangible. The parakite, which resembles an ordinary kite in many details, ascended to an altitude of 1,000 feet or thereabouts, remaining steady while held by the string; but its descent was too rapid to suggest an idea that it would be sale or comiortable for a human being to trust himself to it as a passenger. —M. Treve has submitted to the French Academy a new system of signaling, with the object of diminishing the frequency of collisions at sea. He proposes to employ a signal which will permit the officer of the watch, on perceiving a vessel a short distance ahead, to make known to those on board of her the tack on which he intends to pass her, and that instantaneously. The method by which this is to be accomplished consists in the use of a green or red fire, ignited by electricity, the means of joining contact being close at hand. The green fire would show that the helm is put to starboard and the red that it is pot tr port. This is to avoid the danger •f collisions through both vessels going the same tack.

—According to a writer in the Let Mondee, a valuable method of extinguishing the flames of petroleum consists in applying to them—when water would be without effect—a certain quantity of chloroform, the latter being absolutely uninflammable, and mixed with petroleum in the proportion of one-sixth will render the oil also incombustible.’' More than this, if a litre of petroleum be poured into 8 shallow dish so as to expose the surface of 100 square centimeters, and then ig-

nited, fifty cubic centimeters of chloroform cast upon tlie flames will extinguish them and render the remainder incapable of reignition. In this case, as will lie seen, the quantity of petroleum would be nearly fifteen times that of the chloroform ; and if similar results can be obtained on* a large scale it would be obviously desirable for vessels laden with petroleum to carry also a supply of chloroform. For. notwithstanding the cost of the latter substance as a preventive, it" would of course be more advantageous ,to expend a Reasonable sum in this way than to lose a much larger amount in the names.