NOTES ON SCIENCE MECHANICAL INVENTIONS ETC.

New Zealand Herald, Volume XXVIII, Issue 8664, 5 September 1891, Page 4 (Supplement)

NOTES ON SCIENCE MECHANICAL INVENTIONS ETC.

RFC! ITERATIVE PETROLEUM tAM I*. Mr. Julius Schxklke, of Berlin, has recently constructed a petroleum , lamp which is similar in working to the W enhaui and Clurko gas lamps. The petroleum is evaporated in a chamber, and after having passed thiough a ring of small tubos is burnt as a gas without a wick, and produces an inverted flame. The products of combustion serve for the heating of a system of bailie plates, by means of which the air necossary for combustion is well heated boforo reaching the burner. The flame is perfectly white, and tho regulation of the oil, which flows from a reservoir above, is easily effected by a needle valve, .which at the same time secures the ontranco of a clean oil into tho lamp. The heating of the evaporating chamber is effected by a small flame, which is fed either by petroleum or by spirit, and which is automatically extinguished as soon as tho evaporation of the"oil lias commenced, and the lamp is in working order. Photometric trials show that tho lamp has a high illuminating value per unit of oil consumed. TWO NEW FORMS OF SULPHUR. Two novel modifications of this most Protean element have been recently discovered by Engel, says Industries. Tho first, like that proved to exist in Wackenrodcr's solution, is soluble in water and very unstablo. Tho other is crystalline, soluble in carbon, disulphide and cliloriform, and polymerises slowly in tho cold, and quickly at a temperature of ]00deg (J., bub unlike prismatic sulphur, which changes on keeping into tho octahedral variety, it /becomes converted into tho white insoluble form which commonly constitutes so large a percentage of the material known as " flowers of sulphur." CAUSE OK IRKIDESCEXCE IN OLD OR ANCIENT GLASS. Examples of ancient Cyprian glass ware are noted for their gorgeous irridescence, surpassing in brilliancy of colour anything over produced by artificial means. So far as is at present known, this effect can be produced only by tho corrosive action of the air and moisture of the soil in which these objects have been buried for centuries. A microscopical examination of this glass shows that the surface is covered with exceedingly thin transparent films formed by matter dissolved from the glass. The body of tho glass is pitted over its entire surface with minute cavities, which are circular, elliptical or oblong in outline, and cither spherical, ellipsoidal or cylindrical in respect to their concavity, and the films conform to the pitted surface of the glass. These films, of which there are many superposed, arc so thin as to float in air like down when detached. They decompose the light by interference due to reflections from the front and rear surfaces of the film, and give rise to the gorgeous play of colour. A TURrLE METAL. It is reported, says Iron, that Professor Roberts-Austen has discovered a new alloy of gold and aluminum, the precious metal being present in the proportion of 7S per cent. It is described as the most brilliantly coloured alloy as yet known. Its colour is a rich purple, and by tho reflection of light from one surface of tho alloy to another bright ruby tints are obtained. Other alloys of tho metal with gold have also been known; 1 per cent, of aluminum gives the precious metal the colour of green gold, and there is a very white and hard alloy containing 10 per cent, of gold.

A SUBMARINE BOAT. A submarine boat, says a contemporary, ! is being built in which enough air can be stored' to sustain two men twenty-four hours, using electricity as a propelling power. Why use " stored" air when the water in which the boat is submerged contains an abundance of free air to last " two men" an indefinite length of time? A very small tube with a fine sprinkler attachment, by which a spray of water from the outside can be thrown into tho interior of the boat at intervals, would not only afford an abundance of pure air for tho occupants, but would also absorb tho carbonic acid gas contained in the vitiated air. Avery smail area of tho propelling power would be sufficient to force the water so admitted back to the exterior. Experiments in this direction with diving bells have shown that this method is perfectly practical. Some absorbent of the carbonic acid gas must be employed where compressed air is used. Why not niako use of water for both purposes A GOOD MACHINIST. A correspondent of the American Machinist says There is a good deal of difference between being a good machinist and "knowing the machinist's trade thoroughly." I have been in the business thirty years, but don't know it thoroughly yet, and don't ever expect to ; but I hope I was a " good machinist" twenty-five years ago. There is so "much that is now constantly coming up that one man cannot grasp it all. The best one man can do is to be called a "thorough machinist," which means that he is able to study up ways and means for well and economically doing such work as falls into his hands. Give him a forging or a casting and a drawing, and the thorough machinist can see in tho rough metal the finished work, just as the . culptor can see the perfect statue in the rough block of marble, and knows just how to strike with mallet and chisel to b.ing out the perfect work of art. Just so the " thorough machinist" can see the finished work, and his machinist's instinct and training tell him how to set at work the shop tools to get out of the rough iron the finished work. And so it goes; some young men can make themselves into good ' machinists in six months, some in twelve months, some in two or three years, and some will never get there with the traditional seven years' apprenticeship, and had better do something else; but of all the different kinds, give me the six months' man. He is the one who was " born a machinist," and ho" will continue to learn and become more valuable all his life.

BANANAS AS FOOD AND MEDICINE. Dr. John Dougall, of St. Mungo's College, Glasgow, has a letter in a recent issue of tho Glasgow Herald on the banana.- He quotes from Stanley's " In Darkest Africa," showing that " for infants, persons of delicate digestion, dyspeptics, and those suffering from temporary derangements of the stomach, the flour, properly prepared, would be of universal demand.'* During Stanley's two attacks of gastritis a slight gruel of this flour, mixed with milk, was the only material that could be digested. It is odd, also, as pointed out in Stanley's book, that in most banana lands—Cuba, Brazil, West Indies—the valuable properties of the banana as an easily digested and nourishing food have been much overlooked. Dr. Dougall h"3 made some experiments in making banana flour. He concludes that it should be made from the ripe fruit at its place of production. In trying to make it from bananas purchased in Glasgow, ho obtained, on drying the pulp, a tough sweet mass like toasted figs, an appearance probably due to the conversion of starch into sugar. Bananas contain only about 50 per cent, of pulp, and of this about 75 per cent, is water ; they would yield, therefore, only one-eighth part of flour. MISCELLANEOUS. There is now being finished at Gronville, Pa., a disc of glass for a refracting telescope lens, which is claimed as the largest that has ever been made in the United States. The disc is 3CJ- inches in diameter by 5& inches in thickness, and weighs over 300 pounds. An Italian physiologist of repute, named Mosso, has demonstrated by experiment that thinking causes a rush of blood to the brain, which varies with the nature of tho thought. An English physician has invented a cabinet for the generation of ozone for restorative purposes. The ozone is produced by electricity. It is said that a bunch of clover in a room will rid it of flics. ' Buttermilk contains about the same per cent, of solids as skim-milk. Sulphate or chloride of zinc dissolved in water is a good disinfectant. The bapd saw is fast superseding the circular saw for all kinds of work. The latest application is made by the tailors, who are using it with great success for cutting cloth. ■ A man inhales one pint of air at each breath. While standing, the adult respiration is twenty-two times per minute ; while lying down, thirteen. To save your breath, lie down. An investigation in Switzerland shows that nTortality from organic diseases of the heart decreases as the altitude of the habitation rises, and that it is greater in towns i than in the country.