SCIENCE, LITERATURE, &c.

New Zealand Herald, Volume XVIII, Issue 6147, 30 July 1881, Page 3

SCIENCE, LITERATURE, &c.

Gelatine, che'mica}ly treated, is.the basis' of a new method of: making artificial flowers waterproof, and said to be a close imitation of flowers made of flax.,..- : ;

Helmholtz, the scientist, estimates the duration of the earth ;at 17,000,000 years, the period at which he l considers our sun will have exhausted its store, of heat and become extinct alsso. . ■ - .-... :■- " '~..-'.,■

Herr F. Siemen's. compressed glass has been experimented with at Portsmouth on board men-of-war/ and was found to withstand the shock of heavy guns with compareI tive impunity. ; , ■.-.•■■,■ : - ' Mr. Corby, at a meeting of the Manchester Scientific and Mechanical Society," condemned the screw-jack as a relic of barbarism and predicted that before long it would be superseded by the hydraulic jack. .. . • . A Vienna doctor has invented an electric railway for transmitting letters to great distances, as they are now sent to shorter distances by letter-tubes. In a, short time his apparatus will be exhibited at work in the hall of the Society of Engineers, Vienna. The company in Florida that has been experimenting with palmetto for making paper has met with such gratifying success that it will erect about twenty paper-mills in the State, where palmetto trees grow in abundance and where the transportation facilities are good. Herr Wiedemann has shown that Swedish filtering paper, treated with sulphuric and nitric acid, as in the process for making vegetable parchment, possesses remarkable electric properties. If placed on a waxed cloth, or on the ordinary painted oilcloth, perfectly dry, and rubbed, it will give out sparks several inches in length. During his expedition to Segdu-Sikoro on the Niger, Captain Gallieni made an interesting discovery. He found that near Barmaku, the watershed of the Niger and Senegal basins is only a few miles from the former river. But, what is more curious, the waterparting is so indistinctly marked that during the rainy season the water flows sometimes into one river and sometimes into the other.

Improvements are said to be made in submarine photographic apparatus, by means of which views have been taken near Glasgow, at a depth of 10 fathoms underneath the water. One of these views, taken in the bay of that city, shows distinctly a sandy bottom, with a large number of boulders covered with seaweed, and au old anchor; also,- in the shade, three mooring cables, belonging to small yachts.

WONDERFUL INVENTIONS. Progress is the law of art as of nature. Among recent novelties .is photo-painting, which reproduces coloured photographs on porcelain by mechanical means at a very cheap rate; item, an opera-glass, with camera combined, by which the admirer of a coryphee can transfer in a twinkling limbs in a pirouette to his gallery of favourites without the knowledge of his neighbour in the next stall; and last, but not least, a process by which wood carving can be_ imitated to perfection at a speed.and a price to galvanize the dry bones of Verbruggen and his Flemish compeers in their honoured graves. Even busts can be multiplied in timber with as much correctness as one of Brucciani's plaster of Paris casts, in one hundredth part of the time, and at a tithe of the cost of the original.

A LETTER OF NEWTON. At the recent conversazione of the Society of Telegraphic Engineers and Electricians, held at University College, in honour of the distinguished German physicist, Professor Helmholtz, who is now on a visit to England, a literary treasure of great price was exhibited by Mr. Latimer Clark, C.E. This was a letter of Sir Isaac Newton, which had not hitherto been published. The letter is addressed to Dr. Law, of Suffolk, and is dated London, December 15, 1716. "Dear Doctor," it begins, "He that in ye mine of knowledge deepest diggeth, hath, like every other miner ye least breathing time, and mustsometimes at least come to terr ; alt (terra alta) for air. In one of these respiratory intervals I now sit doune to write to you, my friend. You ask me how, with so much study, I manage to reteno my health. Ah, my dear doctor, you have a better opinion of your lazy friend than he hath himself. Morpheus is my best companion; without eight or nine hours of him ye correspondent is not worth one Scavenger's peruke. My practizes did at ye first hurt my stomach, but now I eat heartily enow, as y' will see when I come down beside you. I have been much amused by ye singular phenomena resulting from bringing a needle into contact with a piece of amber or resin fricated on silke clothe. Ye flame putteth me in , mind of sheet lightning on a small—how very small—scale. But I shall in my epistles abjure philosophy, whereof when I come down to Sakly_ I'll give you enow. I begin to scrawl at five mins. from nine of ye elk, and have in writing consumed ten mins. My Lord Somerset is announced." Sleep then was Newton's best physician, and for all brain-workers it must always be so. The remarkable passage in the letter touching electricity showe us how the extraordinary sagacity of the philosopher detected the analogy between lightning and electricity which Franklin proved long after by his famous kite experiment.

EDISON S INCANDESCENT LAMP.

There was exhibited at the office of the American District Telegraph Company, in San Francisco, one of Edison's incandescent electric lamps. The lamp_ consisted of a handsome upright stand, similar to that of many drop-lights, which was surmounted by a hollow glass l'eceiver, about five inches high. This receiver is egg-shaped, the smaller end resting, on the stand to which it is attached. Into the receiver pass two platinum wires, which pass upward for a snort distance, when they are attached to a horseshoe carbon. This_ carbon, is a piece of bamboo, which,' being cut and bent in the requisite size'and shape, is. carbonized under I great'heat in pressure. It is less than two inches from the base to the top of the arch, and it is hardly, thicker than a piece of heavy letter paper. One of tho platinum wires is attached to one end of the carbon, and the other wire to the other end. There is no air in the interior of the receiver, as perfect : a vacuum as possible having been, obtained. This removal of air was necessary in order to prevent the destruction of the carbon, which would burn instantly when ignited by the electric current if there was'any oxygen : with which it could unite; The wires leading to the stand were connected last night "with an old'ehemicai battery, which .did not'generate much ; electricity, i It was sufficient j in strength, however, to show many of the good qualities of the newMamp. /.To produce a light it was only necessary to turn what looked like the ordinary gas stop-cock;- , ; By turning" it half around thel connection was made-between the wires leading, from the battery and the platinum wires in the lamp and instantly the carbonbecame a white heat, and and gave forth a bright and soft light, equal in power to an ordinary; gas, jet.". The lamp was one of the smallest made, being, it is said, of sixteen'-candlo power. The bght was as soft as that from the.best oil lamp, with no apparent difference in character. It wae evident, however, that the battery was not strong enough to show the full capacity of the lamp. . Wi£h a proper . dectneri • machine ; the result of the exhibition i would have been more striking. Lamps like • that exhibited afe made and sold for Jo cents each, it is said, and Edison claims that each I will last three years if there is no flaw in the , glass or in the carbon, - ■ .~,