SCIENCE AND INVENTIONS.

New Zealand Herald, Volume L, Issue 15375, 9 August 1913, Page 4 (Supplement)

SCIENCE AND INVENTIONS.

FIRE FROM ELECTRIC LAMPS. Recently there was a. firs in a theatre in the city of Settin;; Germany, which was attributed to an ordinary electric hand lamp of the type provided with a wire I guard. The matter was investigated ami! it was found that the- ordinary hand ! lamp provided with a 16 candle-power 220volt carbon filament lamp could cause» a '', fire if brought into contact with sawdust or other equally inflammable material in I such manner that there is little circulation of air to carry off the heaC" But no fires resulted from tests _ with metal fila- 1 ment lamps of equal rating, although in ; lamps of 25 or more candle-powe? ignition | could be obtained. •

TOOTHBRUSHES FROM TREES.

. Natural toothbrushes are ' described in a" consular report from Santo Domingo. It appears that the stems of several shrubs and trees are used .by the natives in lieu of toothbrushes, and aro ; known ras chew sticks." Among them are the r stems' of the orange, the lemon, and the membrillo r or quince tree, all of which have an agreeable flavour. .The most commonly used, however, is a plan', known as " guano," probably the same as the one called -in Spanish " palma de guano." The natives uso the green stem, the end of which they chew up and use as a toothbrush. Various chew sticks are similarly used elsewhere in the West Indies. '

DRIED POTATOES; AS CATTLE FEED.

Germany, is evolving an ever-increasing number of potato products and thus rapidly solving the problem of disposing of the. once enormous surplus of this crop. A number of establishments in that country are now turning out quantities of dried potatoes, in various forms, for use in feeding cattle. According to a recent consular report, dried potatoes do not cause the form of sickness that result from a diet of raw potatoes. Moreover, raw potatoes can, be preserved for only a limited time, while to boil the potatoes wculd impose upon the stock-raiser more expense than the circumstances justify. Official tests have proved that the strengthening food generally given to horses in the form of grain could be replaced by dried potatoes, and such animals would be kept in excellent condition. '-.

STERILIZING SWIMMING POOLS. For the past three years the public baths in the borough :of Poplar, London, have been treated with a so-called " olectrolytic fluid" which in an oxidising fluid obtained by the electrolysis of magnesium chloride. A committee "appointed by . the Royal Sanitary Institute recently investigated the use of this electrolytic fluid and reported very favourably upon it. They found then that when enough of the fluid was added to the water to supply one part of free chloride for every one or two million parts of water, the pool was kept pure and free from odour and there was no tendency for the water to deposit slimy sediments on the floor. This treatment made it unnecessary to renew the water oftener, than once in a week or 10 days.

CADMIUM VAPOUR LAMPS. The mercury vapour lamp wquld be ideal were it not so deficient in red rays. It has been found that by operating th« lamp'at much higher temperatures in a quartz tube there is an increase in the emanation of red rays as compared with green and blue'rays. But even under such conditions the light it gives does .'not possess enough red for ordinary commercial purposes. Efforts have been made to find a vapor which will give the desired spectrum, and the desired end has now apparently been reached by Dr. Waif key who ust-s cadmium in the lamp. The vapour of cadmium give* an excess of red light when the temperature of the lamp is raised, but this is corrected by adding a smjJl amount of mercury. It , is' stated that a lamp of 3800 candle-power uses 620 watts. ~v ■ r ;.';".: : "-:-. ';': " . ,

A MARTYR TO SCIENCE. ; The French zoologist and professor at the Sorbonne, Marie-Yves Delago, who, it was recently announced, has been stricken with total blindness, is the lead ing Worker in Franco on the origin of life problem, and created a stir recently by his . experiments in \ artificial fertilisation, in which- he showed that the eggs of the sea urchin could bo developed Dy i purely chemical means into living specimens. Scientists hail him as a martyr to science, as his blindness is, due to over, thirty years' unceasing microscopic work. Despite his affliction the professor proposes to continue his researches in his laboratory by means of Mile. Goldschmidt, the assistant who has been his right hand for many years. It was in collaboration with this assistant that Professor Delage wrote his book, "The Theories of Evolution,"a translation of which was published last year. ,

ANILINE DYES AND MICROBES.

That aniline colours have a marked action upon various kinds of microbes appears to be established by the recent work of S. Kriegler. Ho studies the effect of a certain number of aniline colours upon microbes such as typhus, coli and others, and finds that aniline compounds in general act to destroy microbes, this beyig even in greater degree than phonic acid. Of the different bacteria he examined he finds that the typhus bacillus is the most readily affected. On the other hand he remarks that not only can there exist differences in microbe-destroying power between the different aniline colours lor the same microbe, which are easily explained by diversity in chemical nature, but he alio notes that the same colour compound does not possess an equally strong power upon different kinds of microbes. In fact, a given aniline colour substance may act as an antiseptic in destroying one species of germs without necessarily being active as regards another species. '.-.,:. ■ / .

HEDGEHOGS AS HOUSE-CLEANERS.

Backwoodsmen, when in camp during the winter, entertain many strange guests —hedgehogs among them. ' One woodsman, it appears, on leaving camp on a Saturday afternoon, used to neglect, purposely, to close the door of his shack in order that the hedgehogs might enter and clean his floor. Inasmuch as the principal constituents of tho camp menu are pork and beans, bacon, and other dishes rich in fat, considerable grease is spilled upon the floor in the course of a week, and a hedgehog will risk his neck at any time for a bit of fat. Just as soon, therefore, as this partictilar camp was deserted by its occupants tho spiny gluttons would hasten in and begin to plane off the surface of the floor with their chisel-shaped teeth, eating away all the wood that held a trace of grease. On his return to camp the owner could sweep up and enjoy the comforts of a clean houso for another week. The only serious objection to this method of house-cleaning lay in the fact that it was necessary to lay a >: ew camp floor rather frequently.

CHEESE ELECTRICALLY MATURED. An industrial electrician of Roll ordain is reported to have discovered a method of giving age to cheese by means of electricity. After a long series of experiments he found that he could take an absolutely fresh cheese and give it all the consistency taste and appearance of a fine cheese that had been stored away "and carefully aged for two years. Ho tikes ;t fresh cheese and subjects ;t to an alternating current. At the end of twenty-four hours of constant alternating electrical currents through the cheese it is said to possess all the properties of a fine two-year-old cheese. This had naturally aroused great interest in Holland, where cheese-making is one of the big industries. It is said the electrician claims he can do many other things with cheese by means of electricity, including an appar atus that will enable the manufacturer to eo graduate and direct electrical action of this nature as to give cheese any taste desired and any consistency that may be needed to supply the wants of a fastidious market.