A SPEED SHACKLE

Evening Post, Volume CIX, Issue 136, 12 June 1930, Page 15

A SPEED SHACKLE

AMERICAN ADVOCACY

MECHANICAL AUTO-CHECK

PUSH-BUTTON DEVICE

In recent years in New Zealand the speed of motor-driving has increased. It may have had something to do with four-wheel brakes. At any rate, there have been people who said that fast driving is safe driving. But in "Roads and Streets," an American publication, Halbert P. Gillette regards it as proven that undue speed is tho prime cause of motor accidents. SPEED FIEND NOT EBTJCASLE. He says that attempts to educate the motorist have failed. Tho motorist refuses to be educated, and continues to drive at fatal speeds.. And tho cure is mechanical speed regulators. This automatic prevention of excess speed is cheaper than traffic constables. And more effective. ■ Here are some of the points he makes in favour of substituting—up to a point —mechanism for, judgment: i The mechanical speed regulator is automatic, but as a rule must first of all be brought into action by the driver, by pushing a button or moving a lever. When the device is operated by the driver, the car shows, a light or signal. This light or signal is evidence that the car cannot at the moment be exceeding a certain speed. Absence of tho light or signal is evidence to the contrary. In a speed-limit district the car thus evidences that it is within the law. Otherwise, it may "or may not be. "There could be two or more speed limits provided on a mechanically speed-regulated car." "Such regulations arc already in use on motor-trucks, whoso owners wish to prevent undue speeding." REDUCES CONSTABULARY LIST. Also "just as 'traffic cops' have been replaced by automatic signals at crossings, so 'motor .cops' should be replaced by mechanical speed-regulators in cars. . . . Under such mechanical control the duties of 'traffic cops' would become mainly duties of inspection of cars, and a patrolling of regions within which speed limits are to be enforced. It woujd require few such traffic inspectors to enforce the use of the automatic speed-regulators." Of course, motorists could still neglect to use their speed-regulators, but it is argued that their failure to do so would bo evidenced by absence of light, or signal. ■ . '. The further argument seems to follow| that motorists who are bad judges of speed would have an automatic cheek to avail themselves of. Faulty judgment of speed, as was recently pointed out in New Zealand by Mr. Justice Blair,, is partly1 mental, because people think in terms of miles per hour instead of in terms of feet per second. To convert miles per hour into foet per second one has only to .add onehalf (50 per cent.) to the miles. .Thus, 20 miles per hour becomes 30 feet per second. Under a mechanically regulated speed of 15 miles per. hour, the motorist, by this simple calculation of adding 50 per cent., would know that he was still j going at* 23 feet per second, and was still capable of killing a pedestrian moving from side-walk to traffic way at walking speed of six feet per second. So the speed regulator would not altogether take the place of the motorist's brain, but tho mechanism's advocates argue that it would greatly assist, and would be at least a step, towards fool-proof achievement. I SPEED-SLAUGHTER EXPLAINED. Halbcrt P. Gillette writes:— ■ "Conversation with motorists shows that few of, them regard increase in speeds as being a contributory cause of the increase in automobile accidents. "But how many motorists know that the kinetic energy of a car increases as the square of its velocity, and that the distance in which it can be stopped by the same application of force increases correspondingly? Add 40 per cent, to the speed and you double the inertia of the ear. You also double the distance required to stop it. "Double its speed and you quadruple its inertia and the distance required to stop the ear. "In the absence of knowledge of this mechanical law, few motorists would have any realisation of the. great increase in accidents that must occur when speeds arc. even ■ moderately increased in any region where traffic is at all (tai.se. That the density of traffic is a big factor is well shown by the fact that during a year traffic deaths increased 43 per cent, in the city of Los Angeles, as compared with 20 per cent, in the county outside of the city."