SCIENCE SIFTINGS

New Zealand Tablet, 26 June 1919, Page 46

SCIENCE SIFTINGS

By "Volt."

Electricity in the 'Treatment of Disease, " Electricity, as ; is ' well known, plays a large part in the treatment of disease, but its usefulness in diagnosing faults and breakdowns c in the human machine is less familiar, except in the 'case-of X-rays for the detection of fractures and foreign bodies. .;■..,.Several ingenious electric instruments have been, invented and manufactured in Great Britain for giving accurate .records of the heart's 1 action and of the temperature of the body. When a current of electricity is passed through the body between the extremities of the limbs, the contraction of the heart alters the strength of the current by an ingenious arrangement this alteration is. made to record itself on a photographic plate. A "cardiogram" is' thus secured which gives a diagrammatic account of the heart's action, and enables the physician to detect conditions which "might escape other means of detection. In taking temperatures, the usual method is to insert a thermometer at intervals and to "chart" the record, drawing straight lines between the points ascertained. With the electric method, the record is continuous, showing the slightest variation from minute to minute. I: :-. Kauri Oil Industry.-. "■ ■■■•?- •'■■--'■ An industry that may be said to be * a direct development of the war is the kauri oil industry. The Parenga Gumfields, Ltd., was formed in 1910, and secured an extensive area of gum lands, the intention being to lease the land in suitable areas to gumdiggers, and so obtain a revenue. The war cleared the diggers out, and the company wag without revenue. Something had to be done, and this something was done. The company experimented with the soil, or dirt, known as puka. This consists of kauri leaves, twigs, bark, etc., which by the lapse of time • have become mixed with the soil, and this dirt : yields a ; very rich oil. Before the war this puka was put into bags and sold at' 12s per bag for export to Germany, and, of course, this business ceased when war was declared.- What' the Germans did with puka is somewhat of a mystery; : but it : is believed that it was used partly for high explosives, and partly in the manufacture 1 of linoleum: The company experimented with the dirt. : A retort was built, and 18 gallons of oil were ■ extracted'from : a ton of puka, and, further experiments following this initial success, resulted in 76 to 110 gallons being obtained. The discovery was later found not to be new; for a similar process was discovered in France before the war for the extraction of oils other than kauri oil. The company having assured itself of the success of the new process, is now installing machinery which will be in position in a few weeks, and will then be capable of producing 4500 gallons of oil, which, when refined, would be worth from 7s 6d to 10s per gallon, because of its extreme richness. If this industry proves a commercial success, as: it is expected' to be, there will be a tremendous opening for legitimate enterprise. There are vast tracts of this . oil-impregnated soil. Puka is found just below a thin layer of sand, 1 and is from one foot 1 to three feet thick, and very many, acres. in extent. , It is below the' puka strata that the gumdiggers look for the coarse kauri gum, which is found in lumps. :■'.'"' " ;j" *' ,'