Scientific and Useful.

Western Star, Issue 871, 16 August 1884, Page 1 (Supplement)

Scientific and Useful.

PRESERVING WOOD. Experiments have for some time been made in Belgium for preserving wood by exhausting the air'.from the pores and fi 1 ling them with liquid , gutta percha. The gutta-percha is liquified by mixing it .with paraffin and subjecting it o heat. After it is introduced into the pores it hsrdens as it becomes cold. M l M ' PAPER. | / > / Some paper-making statistics have recently beep compiled on the Continent hy some busy figure lover, from which it appears that there are 3,9.55 paper mills on the fa 30 of the earth, in Vfliicli. annually 1,904 million pounds of paper are manufactured. Half of this paper is usedfor printing; 601 million! pounds only for newspapers, the consumption of which has risen by 200 million pounds during the la!-4 ten years! As to the use of paper by individuals, an average of, ITJIb is used by an Englishman, 10£lb by an American, 81b by a German, 7alb,by a Frenchman, 3£lb by an Italian or Austrian, by a Spaniard, lib by a Russian, and 21b by a Mexican.— Engineer. WATERTIGHT AND INCOMBIJSTIBIiK FABRICS. M. Dumas has recently patented a process for in .king textile fabrics: watertight and inti imbue title, without making them impermeable to air or allowing them to lose their elasticity and 'softness. This result is obtained by first passing the fabric through si solution containing 7,-8 .per cent., of g< la tine, and; heated ‘to about 40 deg. C. After remaining in 'this liquid for some minutes, the liquid is expressed by means of rollers and the piece is allowed to dry partially in the open air. It is. then allowed to steep • for a few minutes in a.cold solution of alum, containing from 3-4 per cent, of,this salt, after which it is taken but, exposed to the air for one hour, washed in Vpld water and dried. •'„] J MEASUREMENT OF MIND. 'Mr F. (jaitbn, M.A!, F.R.S.) delivered the Rede Lecture at Cambridge recently, taking for his'subject “The Measurement of the Human Faculty.” After briefly : describing the art pf measuring human faculties as the ** dawn of a new and interesting sciepce,” Mr Gal top said .that his new evidence, which he had taken some pains to obtain, showed that the actions of men are “governed by cause and qffect s”. but if the conduct of mau is the result of some external influence, i then such knowledge as he has Obtained Js of little service. Mr Gallon’ oonbluded by sugg sting that ia laboratory should be opened! at Cambridge to investigate this pew science.” An anthropometrical laboratory will be opened at the. Health Exhibition this week .by Mr Galtoc. ’!■ ’ ;:!i • !;> fit y a DANCING-birds; Upon a bare'twig which overhung the trail at a distance of- about four.! feet from - ' the ground,.two mail “Bailadpra ” were engaged in,a “ song and ; dance” act that simply astounded me. Tlie two birds were about a foot find a half apart/ and were alternately jumping about two feet into tlie air and alighting exactly, : upon the spot wlrehoe they jumped. (1 The time was as regular as clockwork, one bird jumping up the instant the other alightedj each bird accompanying bittiself to the tune of “ to-le-do — to-le-do~ — to-le • do,” sounding the syllable “to ” as he crouched to spring, “ le ” while in the air, and “do”as he alighted. This performance .was kept ixp without intermission for more than a minute, when the birds suddenly discovered that they had an audience, and abide off. A HOT REGION. One of the hottest regions of the earth is along the Persian Gulf, where little or no rain falls. At Babrin the arid shore has no fresh water, yet a comparatively numerous population; contrives to live there, thanks to the copious springs which burst forth from the bottom of the sea. The fresh water is got by diving. The diver, sitting sn his boat, winds a great goatskin bag around bis left arm, the hand grasping its mouth; then he takes in his baud a heavy stone, to which is attached a strong line, and, thus equipped, he plunges in and quickly reaches the bottom. Instantly opening the bag over the strong jet of fresh water, tie spriups up the ascending current, at the same time closing the bag, and is helped on board. The stone is then hauled up, and the diver, after taking breath, plunges in again. The source of these copious submarine springs is thought to be in the green hills of Osman, some 500 or 600 miles distant. SPEED OF THOUGHT. < 1 Many people have noticed the remarkable quickness of thought in dreaming, how a long story, with many details and extending over a great period of time, will flash through the mind in a few minutes, but they seldom Have any means of even approximately measuring the quickness with which they sometimes dream. There is now going the rounds of the press a story purporting to tell the dream of a railway engineer, which, if true, ’affords a means of measurement, and the story itself has every appearance of being a genuine relation of experience. The engineer had been without sleep and on duty for many hours, and at last iell asleep on hts post. ■ Then he, dreamed, qftite an elaborate story pf an acpident resulting from a confusion of train orders; how he studied over the words of the despatch, trying to make out their meaning, and then how, his.traiu corning into collision with another, he was thrown into the. air and dropped back iutohis seat in.the cab with his hand on the throttle. At that instant consciousness returned, arid he found that it was all a dream, and that although his train was travelling at the rate of 45 miles an hour, it had gone only 250 feet while the dream was passing through his mind, this distance being fixed by ttie position of the train with respect to signal lights on the line.- This is the interesting part of the story, for if these measurements are approximately correct, the dream occupied less than four seconds of time.-- 'Ledger,

Hurd putty in window sashes may be softened hy applying a hot iron to it.

Besides iron, there are a few other metals which possess magnetic properties —namely, nickel and cobalt in a strong degree, and manganese and chromium in a feebler one. A chain of compressed cakes of gun-cotton tied around the trunk of a large tree and exploded will cut it down instantly by the violence of its action. The cut through the trunk is as sharp as that made by the keenest axel

M. Laborde states in Les Monties that the disagreeable rasping tone peculiar to some violins may be avoided by placing a small strip of wax, on the upper portion of the bridge. The notes are immediately rendered sweet and soft, and can be suited t o the ear by regulating the size of the piece of wax. The highly polished black furniture so much in request ior drawing-room suites is prepared as follows. Smooth wood worked into the necessary form is painted over with camphor water, and then with a solution of su l phate of iron and nutgall; these penetrate and give a black stain. The polisher then takes a piece of smooth, fine-grained charcoal free from grit, and rubs it into the furniture, following his work with a flannel soaked in linSeed oil and turpentine, the result of which is a beautiful polish, and wood resembling ebony*.