Cycling and Motor Notes

Otago Witness, Issue 3265, 11 October 1916, Page 46

Cycling and Motor Notes

BY DEMON.

■ Or:ly about 25 to 30 per cent, of the actual amount of heat generated by the explosion in a motor engine cylinder is transformed into useful work. Losses through the piston Pi.d cylinder walls probably account for quite 30 per cent., whale an even larger percentage is diffused in th l ; exhaust gases. It is conceivable thai wc shall eventually devise a method of utilising nearly all of the exhaust wastage; and to do that it is only necessary to find a means of taking full advantage of the firing pressure—that is, wo must make it do rseful work in the cylinder as long as any pressure remains, instead of releasing it—as. we arc obliged to do at present--while there is still from 40ib to 501 b in tho cylinder. ' But it would appear that all we can do in that direction is to arrange a cooling and radiating system which will maintain the cylinder at the most advantageous temperature, in tho determination of which there are conflicting factors at work, between which a compromise must be effected

Next to the war, tho main topic amongst English motorists is tho serious shortage of petrol. The motorists of England, according to applications rendered to tho Petrol Committee for supplies, have asked tho authorities for 153 million gallons to carry on with, mostly for commercial purposes, and there are only 70 million gallons of fuel arailable in the countr,. Already 75 million gallons had been promised by petrol license, so that even the quantities allotted in this direction by the authorities will have to bo curtailed. Tho general proportions adopted in the distribution of the precious liquid are as follow: Commercial vehicles, 60 per cent, of demand ; industrial processes, 60 per cent.; taxicabs, buses, and other public vehicles, 60 per cent.; doctors and veterinary surgeons full _ amount, up to 50 gallons a month; private, cars, 25 per cent. ; motor cycles, two gallons a month. Tho quantity of petrol to be distributed monthly is 6,300,000 gallons—if it is available. As an inducement to purchasers of motor cycles an English agent advertises that he gives away from six. to 10 gallons of petrol free, according to the class of machine bought. The idea is businesslike; but who would have ever dreamt that things would come to such a pass that tho ff iven-a way-with-a-pound-of-tea principle would one day apply to petrol. Tho recent Italian successes afford yet another example of the successful emergency use- of motor vehicles _ for moving bodies of troops to critical positions, hardly less remarkable than -that of the battle of the Marnc. The Italian commander's plan involved sudden strokes upon tho Austrian flanks. For this purpose, says a recent despatch, infantry were rushed up in motor cars over mountain roads on which the work of improvement and extension had been completed only a few hours before. By this means an entire army corps was moved up from tho plains in the space of 54 hours, being "whirled along at top speed in vehicles of all sorts through the night as well as by day over tho half-made tracks. Accidents were frequent and casualties'numerous; but the troops <>ot there." -A relay of 43 small-powered, lowpriced American motor cars of tho same make recently succeeded in crossing the United States from New York to San Francisco (3331 miles) in 6d 18hr lOmin —equal to an nvcrage speed of 25 miles per hour for the, full distance. Whilst this was a good performance for a cheap runabout, it does not compare with the recent straight-through run by Mr S. 13. Stevens, who negotiated tho samo course in 5d 13j.hr. Among tho small things which servo

to render motoring enjoyable are a speedometer and a timepiece. The first-named is, too, a distance recorder, and it is very desirable tor several reasons to know exactly how far one has travelled —the separate mileage of the tyres, the miles per gallon of fuel ancj per gallon of oil, and, indeed, the distance the car itself has boon driven. As wo know, speed is deceptive, but never more so than when, after moving at, say, 28 to 30 miles per hour, to suddenly reduce

■ to 18 or 20 miles per hour from some 1 ( cause. It is slow by comparison, and were it not for the speedometer, _ with its tellr tale pointer, one would think the engine i was at fault or an incline being breasted, i The distance recorder also takes the place of mile-posts, enabling the motorist to gaugo . ; his whereabouts between towns or junc- • i tions; while the timepiece is good company , at all times, and in the absence of a spoedo- ) meter many drivers can tell their rate

o( travel by tho time required to cover a given distance. What is the position of a man who Uses a car belonging to another man who has not paid the license duty on it? A case in point was heard at tho Lexden and Winstree Sessions (Essex) recently. Ihe car belonged to the brother of tho defendant who was with tho Expeditionary Force m Egypt. The Excise officer stated that tho car was registered by defendant's brother in 1914, and used by him up to the end of 1915, but no tax had been paid on it in respect of 1916. Tho defendant, although it was not disputed that he was not the owner of the car, was convicted and fined 30s,

To really appreciate the quantity of petrol that will pass through a compratively small hole in the fuel-tank or pipe connections the motorist needs to experience the loss, and to find himself stranded on tho high wav a few miles from anywhere. Petrol is a most penetrative and elusive agent, and will percolate through the smallest orifice, and through what does not appear to the eye to be an aperture. In these days of high-priced spirit one cannot afford to allow tho fluid to run to waste, and, apart from that fact, there, is always the fire risk to be considered. The only manner in which a leak in tho tank or connections can be permanently fixed is by tho aid of solder; but it is not everyone who can use a. soldering-iron, nor is there always one available. The method of temporarilv stopping a leak that is usually recommended is to apply soap; but this is far from satisfactory, even where the leakage is very slight. Plasticine is also recommended for the purpose, and, as tho substance is now widely used by children for modelling, a little of it will readily be found in most houses. A writer in a contemporary tells that he stanched a leak in this way! and did 60 miles over bad roads after making tho repair, and 40 miles on the following day, and at the end of the run he found that the plasticine was quite solid and difficult to remove. BRITISH PETROL SUPPLY. According to motor journals from England, published in the last week of July, it appears that users of cars and motorcycles and all other' types of automobiles wore to obtain petrol tickets, without which bo fuel could be purchased. Some_ time previous all motorists had to send in returns showing the quantity they would require. The licenses to obtain petrol cover a period of six months in respect of cars used by medical men, four months in the case of commercial vehicles, and three months in respect to private cars and motor cycles. The restriction of the fuel is general, and the Petrol Control Committee has made such drastic reductions in the quantities desired by the motorists that the latter were deeply chagrined. For instance, tho allowance to motor cyclists, irrespective of the power of the machines, is two quarts a week, but it would not follow that that amount would always be available. Everything apparently depended upon the ratio, of supplies and military requirements.