SHORT ARTICLES.

Hastings Standard, Volume XIII, Issue 4310, 13 November 1909, Page 2 (Supplement)

SHORT ARTICLES.

EDISON S CEMENT HO USES. Much newspaper comment and expert discussion regarding Edison's "poured concrete house" has been indulged in i'or over two years, most of it based on fragmentary info motion.. The "Cement World" furnishes the needed details in an authorised interview with Mr. Edison himself.

He has produced a mixture of a con-

sistency almost like water which holds the stone or aggregates in suspension, allows the mixture to flow freely to all parts of the moulds and secures a uniform distribution of the aggregates throughout the mass. The moulds are adapted to variations of arrangement, thus making it possible to chang the style of houses with the same set o f moulds. With five or six sets of moulds, therefore, a wide variety of style is possible. Cast-iron moulds will be used, set- up on a concrete foundation or footing, and some time before the moulds are set up this footing and the basement floor.will be placed in order that they may be thoroughly -set before the moulds are erected.

The moulds will b? placed on this footing, and the cast honse will include the basement walls. Decorations will also be cast with the house.

The time necessary for the pouring of the liquid he says will be only six hours. Four days after the pouring the dismantling can lie done. Six more days are allowed for the hardening of the concrete.

The inventor thus makes fourteen days as the time necessary for the completion of a house—a house both fire-proof and damp-proof.

The cost of a house. three storeys high, will hp, roughly speaking, about £2o(), and Mr. Edison says this will include heating and plumbing and a structure rencly for occupancy. Ho lays special emphasis on the fact that this price is based on the building of houses in large numbers where materials can he purchased in large quantities and where the gravel ex'avated 011 the site can be used in the mixture. WHY PEARLS ARE FORMED. The near I is made by the oyster against its •will, and is the result of an injury which the mollusc has suffered at on© time or another. It has been ascertained that a tiny parasite makes its abode with the oyster. In time this little inse.t works its way out again, but before doing so it forms a small, bard cry.st 011 the inner surface of the shell.

This cryst -irritates tlTe oyster very much, and it deposits on it layer upon layer of a. thin, almost transparent coating, which finally gives us the pearl of price. Pearls are formed without the aid of the parasite*, but bv an injury to tlie shell. HOW WIRE IS DRAWN. The following is the method generally followed in making or drawing wire. Bar?, of metal four inches square are heated and passed while hot and plastic through rapidly revolving rolls, reducing them to wire rods which vary from one-quarter of an inch to an inch or

more in diameter, according to the size of wire wanted.

(These rods, which arjv formed into coils as they pass through tho rolls, are dipped in acid baths to remove loose scale and provide a lubricant for drawing. Drawing consists of pulling reds while cold through holes of graduallydecreasing diameter drilled in steel plates. During the process the particles of metal become elongated and strained, making the wire harder and more brittle. To restore it. to a proper temper it is necessary to heat or anneal it.

Wlien a fine diameter is required there must be repeated annealings and drawings. This may be done until the bar, which was originally four inches square and lour feet long, becomes reduced to a diameter of a single thousandth of an inch and extended about 13.000 miles in length. Before so fine a size is reached, the wire will cut into tho steel of a, die plate, so the usual die plates must be discarded and the drawing continued through holes drilled in diamonds, the diameter of these diamond dies decrease so gradually that the perspective is to bo reckoned by fractional parts of a thousandth part of STi inch.