SCIENCE NOTES & NEWS.

Matamata Record, Volume II, Issue 105, 7 November 1918, Page 3

SCIENCE NOTES & NEWS.

JfTHE MANUFACTURE OF WINDOW GLASS. Window glass is blown.in the shape of long cylinders, which are cut open along one side and then placed on a stone in a hot furnace, where they gradually collapse and flatten out into a big sheet of glass. Often the glass breaks during this process, or even explodes, forming thousands of pieces, which shoot in ail directions. A NOVEL FIRE EXTINGUISHER. ' Ammonia bombs as a means to extinguish forest fires are being tested In some of the-, national- forests of America. In the case of bush fires, ' the fire-fighters often have difficulty in getting near enough to beat out the flames, and ammonia bombs have been found very effective The explosion of a single bomb will extinguish fire in a fifteen-foot circle. A NEW GASOLENE STILL. A small still has been designed by means of which a motor car owner may convert four gallons of crude oil into three and a half gallons of fuel in two hours. The oil is placed in the lower part of the still and heated by means of a burner underneath, this burner being fed by gas or oil. The vapour arising from the heated oil Is condensed in cooling coils and drawn off at the side into any suitable tank or vessel. LAND RECLAMATION IN HOLLAND. The reclamation of land in Holland" •—a task that has been prosecuted steadily for centuries—is still going on actively. From twenty to twentyfive thousand acres of land are reclaimed every year. It is said however tk,at more than two hundred and fifty thousand acres of the best soil are still under water, not including the great area under the Zuyder Zee, the reclamation of which is a perennial topic of discussion. y A ROYAL AMBULANCE. Some time ago, the Queen of Bulgaria, who takes a great interest in the Red Cross Service, had built for her a special ambulance motor-car, • and It was used in the field during the war in the Balkans. The roomy body of the limousine type is arranged In two compartments, one on each f- side. On the right hand side are lodged two stretchers, cne above the other, which can be run in by means of rollers through a back door. The other side has two, seats for the aids, and is also reached from the back, there being also two side doors. As the side door in the stretcher compartment can only be opened from the outside, it is impossible for patients to leave the ambulance unawares. Ground-glass panes give sufficient light while preventing the interior from being seen from the outBRIQUETTES. , In France, with brittle coal, there are twelve million tons of briquettes made yearly; in Germany, with soft brown coal, there are sixteen million tons made; but in Great Britain, only two million tons are produced, and these mainly in South Wales, where the dry coal briquettes more easily than the greasy English coal, which needs a strong binder. One reason for this is that the English colliery owner gets rid of his slack with the lump. He could get more for his coal were it clean and Avithout slack, but that would leave slack on the colliery owner's hands. Were it not for hia lack of enterprise he would sell his coal clean, getting a higher price for It, and turn his slack into briquettes. To do this, however, it would be jiecessary for the tar distiller to make a pitch suitable for the purpose. 'At present this is not done, as the distiller is not encouraged, there being no demand for such a pitch. .. A STUDY OF STRENGTH. A medical authority states that the inuscles, in common with all organs pf the human body, have their periods of development and decline, our physical strength increasing up to a "certain age, and then decreasing. Tests of the strength of several thousand individuals have been made, and the following figures are given as the averages derived from such tests: — The lifting power of a youth aged seventeen years is two hundred and eighty pounds; in his twentieh year this increases to three hundred and twenty pounds; and in the thirtio':h and thirty-first years respectively it reaches its height, three hundred and sixty-five pounds. At the expiration of the thirty-first year the strength begins to decline, very gradually at first. By the fortieth year its has decreased eight pounds, and such diminution continues at a slightly Increasing rate until the fiftieth year is reached, when the figure is three -hundred and thirty pounds. Subsequent to this period the strength fails . more and more rapidly, until the weakness of old age is reached. It is found impossible to obtain trustworthy 'statistics after the fiftieth year.