SCIENCE OF THE DAY.

New Zealand Herald, Volume LXV, Issue 20088, 27 October 1928, Page 7 (Supplement)

SCIENCE OF THE DAY.

AN ENGLISH MOUSE FARM. Animals loathed by thousands aro carcfujly reared and tended at a. farm in Essex. Fifty thousand mice is tliq stock of, a farm at Itaylcigh, appropriately named " Tlio Mouscry." Iheie are brown mica in thousandsj_, tlicio aio creatures with coats of silver, lemon, pure white, and lawny. All are housed in comfortable cages made of condensed milk boxes and wivo mesh,'and 'daily, from two in tlio afternoon until seven, Mr. luck, the farmer,: and his two assistants aro kept busy feeding tlio mico with bread, milk anil" corn. All tho cages arc labelled, and at a minute's notico the {armor can produce mice of any breed. Each mouse is bred for a purpose to assist scientists and others to conquer cancer. Every week largo numbers of mico aro sent to London and distributed to schools of medical research, hospitals, and so where they aro used by scientists in their experiments. Mice used for research work must bo absolutely hfealtliy, and to maintain stamina wild mice aro introduced into tho stock from time to timo. ' Tho important part these creaturos play in' tho medical world recalls tho purpose they served in the war. when hundreds of lives were saved from gas poisoning becnuso of the effect gas had upon mice. They are still being used to detect foul I gas in coalminos and sowers.

SULPHUR IN SOIL CULTURE. A plant in order that it may live and develop normally must lmvo at its disposal ten simple elements. These aro carbon, hydrogen, oxygen, nitrogen, phosphorus, potash, calcium, magnesium, iron, and sulphur. At present most of these essentials aro supplied by specially prepared fertilisers;' hitrogon for example,' is distributed in tho form of sulphate of ammonia, phosphorus in basic slag and supcrphospuato, potash in kainit. and sulphate of potash, while calcium is given in tho form of lima or limestone. As u result of carefully organised research, tho functions of tlieso different nutritive elements lmvo been fai'ily well established. It is now known, for instance, that nitrogen gives tho body to a plant and that potash is necossary to the formation of starch in potatoes or sugar in beet- It is only of recent times, however, that

tho physiological valuo of sulphur in plant life and soil culture, apart from the knowledge that it is an important constituent of proteins, has been, mado quite clear. In certain parts of America it has been demonstrated by practical experiment that crops such as lucerne and clover benefit enormously by an application of sulphur in tho form of sulphate. The probable reason for this phenomena is that the bacteria in tho sub-soil transform sulphur into sulphuric ncid which attacks and renders assimilable tho insoluble phosphate 'and potassic compounds of earth. SILK FROM CABBAGES. Although most artificial silk fabric is made of wood pulp, it can also bo made from cabbages, bananas, or any other vegetable matter from which cellulost/ is obtained. Pcoplo can usually tell the difference between puro and artificial silk by squeezing it up in their hands. Real si lk, unless weighted with chemicals, feels warm to tho touch and will not creaso. Artificial silk feels cold and slippery, besides being too lustrous. Its creasing propensity is one of tho greatest problems for manufacturers, ana manv experiments aro being tried to copo with tho difficulty, and save women tho trouble of hiving to iron an artificial silk frock each time it is worn. WORLD'S QUIETEST SPOT, A silenco ncarer'absolute than that of the uninhabitated mountain peaks or Arctic wastes has boon obtained in a room at tho University of Utrecht, in Holland, It is tho world's most soundproof room* and was designed to test the behaviour of human oars in experiments that would bo ruined by tho slightest accidental noise. It ia built like a thermos bottlo, for it is a room within a room. The air has' boon pumped out of the space between its double walls to form a vacuum, while tho walls themselves arq made of alternate layers of lead, ,wood. and felt.