HIGH ROAD AND BY-ROAD

Waikato Times, Volume 124, Issue 20740, 25 February 1939, Page 14 (Supplement)

HIGH ROAD AND BY-ROAD

i A COLUMN FOR MOTORISTS. j

REDUCING CAR MISHAPS VAI.I'K OF TRAFFIC LIGHTS NF.W YORK STATISTICS The value o' traffic 1 isrTi 1 s In refiueing rilv accidents was demonstrated in N>w York reccnlly. In an effort to minimise traffic accidents in that city in the early morning hours, the authorities derided to operate the Iraffle lights right throughout the night hours.- Refore the order became effective. traffic lights were turned off between 3 and 7 a.m. The first morning that the new system came into operation, only one accident was reported. compared with the former average of seven. According to statistics issued by the New Yorli Safety Council, 5 per cent, of all motor fatalities and 3 per cent, of all non-fatal accidents in that city occurred during those four early morning hours, although the volume of traffic was relatively small, hence the test hy New York authorities to see what effect leavinc the traffic lights in operation had. The outcome has been a sharp reduction in mishaps. TYRE INFLATION EFFECT ON WEAR WHAT TESTS REVEAL Two intoresllne facts were recently revealed in a paper about tyres presented bv Mr C. D. Law, of the Dunlop Companv (England) to the British Institution of Automobile Engineers. “Dther things being equal.” said Mr Law. “a drop in inflation of one per cent! in the pressure of a motor tyre of the balloon type results in an increase in rate of wear of 1.3 per cent. That is to say. a pressure reduction from 25 lVts. per square inch to 20 lhs. per square inch (20 per cent.) results In an increase in rate of tyre wear of 2fi per cent. Tn relation to motor car deceleration tests conducted in the company’s testing department, tt was revealed there Is definitely and unmistakably a reversal of acceleration as the vehicle comes to a fairly sudden stop. It seems that the car flicks itself back, and in fact, this is fust about what happens. During sudden braking, part of the weight of the machine is transferred from the back axle to the front. When the ear slnns. just tile opposite occurs to get hark to normal. Some people declare this kick-hack Is imagination nr a psychological effect or muscular reaction, but according to the tests conducted hy Dunlop experts, deceleration charts, registered by an Instrument which measures at any instant the acceleration and deceleration of a motor vehicle, reveal that there Is a slight reversal of acceleration when car brakes are applied hard.

OIL CONSUMPTION FAST V. SLOW SPEEDS INTERESTT'NO TEST? To ascertain what different driving methods havo on petrol ronsumpfion. an ini eresfing lost was conducted in London recently. Throe 12 h.p. saloon ears, identicallv eauipped, were chosen for the demonstration. Prior fo the test, the respective tanks were drained of petrol. They were then refilled from Government stamped measures, and the ears driven 200 'miles alone: the London to York road, which carries a heavy volume of traffic. One car travelled at an average speed of just, under 35 m.p.h., and the others at approximately 25 m.p.h. and 49 m.p.h. respectively. At the conclusion of the runs, the remaining petrol was drained from the tanks and a fra in measured. The resultant petrol ronsumption figures indicate very vividly to what extent- fuel economy is affected hy methods of driving. The ear that averaged 25.13 m.p.h. recorded 33.06 miles per gallon: the machine that averaged 34.69 m.p.h. covered 32.02 m.p.g., while the fastest, f ♦ravelling vehicle, which averaged : 49.64 m.p.h. travelled 22.39 m.p.g. i These figures are enlightening, says i the nunlop Bulletin, and show how [varied petrol consumption can be I while motoring on a. normal main road in a family saloon car of medium power.