Rensselaer Union, Volume 8, Number 16, Rensselaer, Jasper County, 6 January 1876 — MECHANICAL AND SCIENTIFIC. [ARTICLE]

MECHANICAL AND SCIENTIFIC.

—The success attending the use of nickel as a plating material has promoted experiments in the use of other hietals for a like purpose. The latest of these is that reported by Bertrand, who lifts succeeded in producing a galvanic deposit of bismuth on the surface of other mAals. The process may be described as follows: From twenty-five to thirty-five grains of the double chloride of bismuth and ammonia are dissolved in about one quart of water, and this solution is used cold, by the usual methods, a single Bunsen pile being employed. On coming out of the bath the coated surface is covered with a dark-looking slime, beneath which the metallic luster of the bismuth is visible. This latter adheres very closely,-and takes a fine polish, the color being intermediate between antimony and silver'— Scientific American.

—To prevent rot in timber nothing is better than a thorough seasoning, with proper ventilation. Charring' timber, or creoso(ing it, will do much to arrest decay ; but when once the dry-rot is found a cure becomes necessary if we cannot remove or replace with new. A pure solution of corrosive sublimate in water, in the proportion of an ounce to, a gallon, used hot, is an effective remedy. A solution of sulphate of copper, half a pound to a gallon of.water, laid on hot, is recommended as another cure. Paraffine oil, or the cheapest naphtha oil, will stay the decay. But the fundamental philosophy of the whole question of timber preservation lies in a nutshell. It is the evaporation of the juices and moisture —in one word, seasoning; after which it is only necessary to protect the wood from moisture from without.— American Builder —A substitute for leather, of English manufacture, was displayed at the recent Maritime Exhibition in Paris, and received with much favor. It was composed of a layer of cork between two layers of textile fabric, the whole beinir gummed with india-rubber and welded together. Thej process by which it is manufactured is as follows: Thin sheets of cork are painted upon one side with two successive coats of india-rubber. Japanned clothcanvas is treated in the same manner, and when dry its gummed surface is applied to that of the cork-sheets. The clean side of the Cork is now treated with two coats of the india-rubber; and a linen or cotton fabric, after subjection to the same process, is laid upon it, the coated surfaces coming together. The compound sheet is then submitted to heavy pressure between rollers, or under a stamper, or press, until it is in effect a simple substance, having strength, durability and flexibility. Some one has remarked that the times are so close just now that even the days are “short.” —Extensive revivals are reported in the Baptist churches of Richmond, Va.