SCience Siftings

New Zealand Tablet, Volume XXXIV, Issue 26, 28 June 1906, Page 29

SCience Siftings

By «Volt*

A Land of Perpetual Ice. The largest mass of ice on earth is beyond the control of the Ice Trust. It has been accumulating in Greenland for thousands of years, and the immense block is supposed to a/erage a mile and a half in thickness, its aiea being about 600,000 miles. Above Sea-level. Of the 58,324 square miles of England and Wales, Miss Nora MacMunn finds that .26,482 are under 250' feet in elevation above the sea, 16,365 are between 250 and 500 feet ; 10,476 are between 500 and 1000 feet ; 4698 are between 1000 and 2000 feet ; 30.0 are between 2000 and -3000 feet ; and 4 are more than 3000 feet. Remarkable Effect of Violet Light. Ultra.-violet light is claimed by Professor Kronmayer, a German experimenter, to have had remarkable effect in the treatment of falling hair and baldness. In thirty-two cases where e\ery other remedy had failed tha light rays oured twenty-seven, and not only the hair, but in some cases the eyebrows and beard were restored, although 'the trouble was mostly of long standing. A Substitute for Leather. The general increase in the price of boots in England has had the effect of bringing forward many substitutes for leather (says a London paper). The high rates ruling for hides and skins in the English, American, and Continental markets have led a number of ingenious people to experiment with various kinds of substitutes for leather, but as yet no satisfactory substitute has been seen on the open market. The most prominent of these substitutes for making the boot uppers takes the form of a finely-woven fabric, considerably finer than any of the canvas materials at present used for seaside shoes, but it lacks the surface finish and appearance of leal her. The waterproofing difficulty can te got over, and it may in time be so far improved as to enter into regular consumption for cheap goods. Novel Water-pipe Protector. Water. pipes are usually protected from freezing by the use of such non-conducting materials as straw, cork and oakum, In a new h rench method, a layer of straw, sawdusit or tan-bark is first placed around the pipe, and pieces of unslaked lime as large as the fist are then packed around this coating and enveloped in a layer of non-conducting material, the whole being held together by a wrapping of coarse linen. The inside layer serves simply to protect the pipe from corrcsion by the fresh lime. The outer covering admits only a small amount of air, and the moisture in this acts on the lime, which becomes warm and is so slowly slaked that the heat may be kept up during an entire winter. Frozen pipes may be thawed by using somewhat more lime and slaking rapidly by pouring 1 water over it. About Looking Glasses. The earliest looking glasses, or mirrors, were cf either metal, highly polished, or of black painted mica. It is noted in Jewish history that the layer was made of brass 'of the looking glasses of the women who assembled at the door of the tabernacle of the congregation,' and some commentators conjecture that these women gave lip \ thfeir bronze or copper hand-mirrors to supply the material of the layer. Egyptian women always carried their mirrcrs to the temples, and the Hebrew women probably did likewise, as do the Arabian and Turkish women today. Glass mirrors are of comparatively recent date. Mirrors of sil-ver and gold were commonly used in mediaeval times. In 1360 Venice became the seat of the manufacture of glass mirrors, which have since superseded all other varieties ; the improvements in the man-ifacture of plate glass enabling mirrors to be made of great size.