Science Siftings

New Zealand Tablet, Volume XXXIII, Issue 37, 14 September 1905, Page 29

Science Siftings

By 'Volt'

Thei deepest gold mine in the world is the New Chum Railway Mine, Victoria, in which a reef has been discovered at a depth of 4Uk;4it. Tbe disco\ery is oonswlered of considerable importance, inasmuch as it is an evidence of goM at greater depths than was generally supposed to be the case. Pure Milk. Milk as it leaves the cow (writes ' Medicus ' in the * Argus ') comtt/ns no germs of any kind, it is not only sterile,, bub has probably a slight bactericidal effect. All germs are introduced after the milk has (been exposed to the air. The question that putxlic health authorities are endeavoring to solve is hoiw to keep milk as nearly as possible in its ori'gdnal condition until it reaches- the consumer. At first, various processes of heatingi the mil* were advocated, from pasteurisation (which was introduced bjy Pasteur, and consists of hfcWUnjgi tfiej milk to a certain point) to sterilisation, in. which milk is boiled or exposed to temperatures higher than foiling point. Sulbsctjjaenl observation has revealeldi that tbe first process is unreliable and the second, undesirable, since sterilisation considerably alters the nutritive property of milk. At the present time the three requisites are generally admitted to consist in clean hplidling, rapid cooling of tiie milk to 4Odeg. Fah. immediately aftefr fcieing milked, and qbick transit. The Guinea. It is \ amongi things generally known that the gfuinea obtained its name from the gold from which it was made hawing been brought from the Guinea Coast by the African company of traders. The first notice of this gold was in 1649, during the Commonwealth of England, when on the 14th of April of that year the Parliament referred to the Council of State a paper presented to the House concerning the coinage of gold brought in a ship lately come from ' Guiny ' for the better advancing of trade. But it was in the reign of Charles 11. lifaat tha name was first given to this coin It is among things not generally known that when the guinea- was originally coined the intention was to make it current aa a twenty-iSihilling piece ,- but, from an error, or rather a series of errors, in calculating, the ex>acb proportions of the value of gold and silver it never circulated for Ifoat value. Sir Isaac Newton' isj. his time, fixed the true value of the guinea, in relation to siher, at 20s M, and by his advice the Crown proclaimed that for the future it should be current at 21s. Coal Tar Products. When coal gas was first introduced as an illumjnant for largie; towns the tar whioh is condensed from the gas was looked upr-n as a nuisance. However, chemists discovered that coal tar was an exceedingly complicated compound and lent itself admirably to' the production cf a gircat number of useful chemicals. So we find to-day that all the various brilliant and beautiful dyes employed far coloring various kinds of fabrics are produced from this substance. Coal tar also furnishes the basis for sci/eral kinds of medicines, such as trional, sulphonal, and so on Saccharine, which is a substitute for sugar is also made from coal tar. Carbolic acid (phenol), the most hnrartlant and best known antiseptic find disinfectant is a product of coal tar. Benaoi, a clear and colorless liiqiuid reFemfylinK alcohol to some extent, is another distillate which is omployed for removing crease spots. ° b Then we have naphthaline, a substance which to some extent resembles camphor, and is employed, like camphor, to protect woollen fabrics from moths