FICTITIOUS SPEEDS.

New Zealand Herald, Volume LXIII, Issue 19275, 13 March 1926, Page 12 (Supplement)

FICTITIOUS SPEEDS.

INACCURATE INDICATIONS. Road tests, conducted in England, of dozens of makes' of new cars have revealed that the majority of manufacturers are putting their cars on the load with the speedometers reading from 5 to 10 per cent. fast. Timed over a measured distance the car with an apparent speed of 50 miles an hour may be incapable of move than 47 in.p.li. From every point of view this inaccurate setting is to be deprecated. One manufacturer who has a large output sets his speedometer drives so that his cars have a fictitious speed of 55 m.p.h., representing an actual 50 ra.p.h. The producer of a car of similar power then finds that comparisons are being made, and that his car is tlm slower. He then sets his speedometer drives to read too high. Many of these speedometers are very liigh-class instruments, and they cannot bo blamed for the unreliability of the indicated speeds. When it is found that the error is present in the same proportion at all speeds, it is obvious that the drive ratio is wrong. Some of the cheapest speedometers are fitted with nn excess reading because they tend to run slow after usage. It is obvious, however, that some precision instruments are deliberately over-geared to givo a false impression of the car performance and benzine consumption. EXPLOSION MYSTERIES. STATIC ELECTRICITY BLAMED. All students of electricity are familiar •with simple experiments showing the effect ox static electricity. ' Sparks can be produced by friction in innumerable ways. Lately static electricity is being blamed for many petrol explosions. Liquid petrol is not dangerous in itself. Confined in a tank or can, it is quite harmless. But the gas it gives off, combined in proper proportions with air, makes a highly explosive mixture. Scientists have determined that the iguited vapour from a single gallon of petrol can pioduCe an explosive force equal to 831b. of dynamite. One can imagine the devastation which -would result if the contents ot one of the. 1000-gallon motor tank waggons which 1 are seen "serving Bowser pumps were fired. Petrol rushing through the hose at a petrol pump -generates static electricity, which passes through the metal nozzle into the metal parts of the car. There it is stored up because the car is insulated from the ground by rubber tyres. Touching the car with any conductor of electricity will cause the static to bo discharged. The hand of the attendant or tlio tioso nozzle, as it is withdrawn from the tank may supply such a conductor. The resultant static spark, occurring over an open gas tank and near a spot where a quantity of petrol is spilled every day, is bound to be mors or less dangerous., HIGHER SPEED LIMITS. " The current type of automobile with four-wheel brakes and easy steering is flexible and secure at speeds of 35 miles n#i hour," says Mr. E. T. Strong, general manager of the Buick Motor Company. " Traffic regulations are much the same as they were when cars were not built up to present-day standard,"' he says. "In most states laws could be modernised. By failing .to keep up the speed limit on country highways, the slow 1 driver causes a general paralysis of traffic which augments congestion and makes all driving mora dangerous. A penalty on the slow driver should help, to . relieve this con dition." ' "' RIDE ROUND U.S.A. Youthful patriotism inspired the 16,000mile motor-cycle ride round U.S.A., from which Brian Rhodes, 17 years of age, of -Melbourne, Victoria, has just returned. In San Francisco he bought a secondhand Indian Scout, placaded it with " Australian, aged 17, travelling round America," and set out. Ignoring a fund of money at' San Francisco, he determined to work his way round. Battling along, his riding time heavily curtailed by the necessity to work, ho* got back to San Francisco after 14, weeks, hatless and hungry. Most of his earnings cama from wood-cutting. For a night he worked in a canning factory and earned two dollars which soon went for oil ' and petrol. At a town in Nebraska, he entered his Scout for a five-mile speed dash at. a County Fair and won a trophy that kept him lor.'four days. All the way he resolutely refused charity. One bitterly cold night in. Montana he slept out in the mountains,- 6000 ft. up, with only one blanket for bedclothes, rather than beg a bed. In Texas his adherence to principle made him declinethe offer of a motor-cycle dealer to overhaul his machine free. At one stage he parted with his horn to pay for petrol. Most of his tools he turned into money for the same reason, and he travelled 16,000 miles with only a pair of pliers in his tool kit. It was a tough ride, a rido that bared him to the keen edge of privation and suffering, but, now that he is home, all that matters is " that he has earned his way round America, has visited evry State in the Union, and has given Australia quite a lot of publicity on the way. MOTOR PUBLICATIONS. A handsomely-bound and illustrated book, "Around the World with Texaco," is being distributed in New Zealand to secondary and technical schools by courtesy of the publishers, the Texas Oil Company. The book has been compiled by a representative of the company, Mr. C. S. Dennison. It contains much interesting information concerning the customs and characteristics of various nations.