Rensselaer Union, Volume 8, Number 5, Rensselaer, Jasper County, 21 October 1875 — MECHANICAL AND SCIENTIFIC. [ARTICLE]

MECHANICAL AND SCIENTIFIC.

—The fluidity of the Berlin iron, from which the finest and sharpest, although not the strongest, castings are made, is attributed to the presence of arsenic in the iron. —ln relating his, experiments with insectivorous plants Dr. Moore, of Glasnevin, states that in one instance he found in a single pitcher of a Nepenthes the remains of ninety-one ants, sixteen wasps, four large blue-flies, one cockroach, five earwigs and seven wood-lice—in all 125 insects —besides a putrid mass of the dead bodies of creatures too decomposed to be recognized. —An engine has been invented in Paris which is driven by the alternate expansion and contraction of oil or some other liquid, contained in cylinders. The liquid is heated so as to expand by the application of hot water passing through small tubes, and cooled so as to contract by means of a refrigerating mixture similarly applied. —A French. machinist has discovered that, by keeping his turning tools constantly wetted with petroleum, he was able to cut metals and alloys with them, although when the tools were used without the oil their edges were soon turned and dulled. The hardest steel can be turned easily if the tools be thus wet with a mixture of two parts of petroleum with one part of turpentine. —Among the. most interesting conclusions arrived at, recently, by those astronomers who have specially directed their attention to the solar spots is that, during periods of great disturbance, there is a tendency in the spots to change alternately from the northern to the southern hemisphere, and vice versa, the period of such change being about twenty-five daj s. On the other hand, jt is only when the solar disturbance is inconsiderable that the spots do not present any such systematic oscillation. Connecting this generalization with previous discoveries, it is regarded as demonstrable that outbreaks probably occur in pairs, at opposite ends of the same solar diameter, at an interval of twelve or thirteen days.— Exchange. —lt is a peculiarity of human nature that, just as bethinks he could runanewspaper, every man thinks he knows just how an election is going.