SCIENCE OF THE DAY.

New Zealand Herald, Volume LXIV, Issue 19744, 17 September 1927, Page 5 (Supplement)

SCIENCE OF THE DAY.

WORK OF THE BOTANISTS.

That in many parts of South Africa vegetation is gradually receding is the view expressed by Dr. R. Marloth, M.A., Ph.D., who has just been permanently attached for special research work to the South African Union Division of Botany. His remarks have a general import in all countries. Even the Government, he says, does not realise how much more there is to be done in botanical research in South Africa. The future of the country does not lie so much in the gold or diamond mines, whose life cannot bo prolonged for ever, but in the vegetation, natural and artificial. The higher powers who were directing the destiny of South Africa and the public generally, Dr. .Marloth continued, did not sufficiently realise that the trend of natural events seemed to be against man. Things were on the downward slope, and if man did not assist the forces of nature by studying vegetation the results would" be disastrous in years to come. Tl>at could be verified by the pushing back of the Cape flora and the belt where it touched the Karoo. Even within the past ten years there had been a noticeable, gradual change going on, the vegetation receding all the time. Dr Marloth said that they needed no severe period of drought to show that, although never before had it' been necessary to help the people living there as the" province now had to do. It was the department's duty to enlighten people on vegetation and kindred matters. Some scientists grabbed all the information they could get and " sat on it." The majority of botanists delighted in discovering new species, and it a special charm to their work. But they rnnst work for the benefit of mankind and combine their forces, and the individual discoveries should be imparted to others. AN AUTOMATIC TIMEKEEPER. At a race meeting at Cape Town a few weeks ago a wireless invention, an automatic timekeeper, was completely successful. It is worked by an invisible ray from a lamp in the judge's box focussing a point of light one-fifth of an inch in diameter on a selenium cell fixed in the winning post. Anything crossing the invisible ray extinguishes tho point of light and the clock ceases.

A MECHANICAL BRAIN. One of the latest marvels of science is a machine which can make the most intricate mathematical calculations, but un like human arithmeticians, it cannot make a mistake. It adds, subtracts, multiplies, and divides when a typist manipulates an electric switch. If the typist presses the wrong key or makes any mistake the machine stops working. Bat that is not all. The machine is even so clever as to ba able to indicate in which column of figures the typist made her error. Decimal " sums"—as a schoolboy would say—and problems of simple interest are solved with amazing ease by this mechanical imitation of a human brain.

THE METAL AEROPLANE. Although in outward appearance_ aeroplanes have changed hardly at all in the last teti years, there have, in fact, been great developments. One of the chsef moves has been in the gradual change over from wood to metal in the structure, which has been largely due to the fear of a world shortage of the special types of timber suitable for the exacting demand!! 'of aircraft construction- Incidental to this change has been the development, as a result of a peat deal of experimental work, of metal hulls for fiving-boau. In this particular direction the most suitable material ha* been fc*md to be not steel, but one of the aluminium alloys such bs " duralumin." This has two important advantages over wood. In the first place the hull actually comes out lighter—in the case of the Super marine Southampton, the standard twinengined reconnaissance machine of the fleet air arm—by as mtsch a* 5001b. In addition to this, however, the metal hull does not absorb the water as wr<?d does After a few months' service a wooden built d Southampton will have soaked op enotsgh water to increase its weight by 4001b The result of this cotnVfed saying, amounting to a total of SQOfh. is that the service range of the machine, carrvinst the same crew am! armament, is increased by the striking figure of 200 miles.