NOVEMBER 30TH, 1907,
THE AUTOCAR B Journal publtsbet, in tbe interests of tbe mecbanicall\? propelleb roab carriage.
EDITED BY H. WALTER STANER.
No. 632. VoL. XIX. SATURDAY, NOVEMBER 30TH, 1907. LPRICE 3n.
THE A UTOCAR.
(Published W eekly.)
Registered as a newspaper £or tra.nsmi~sion in the United Kingdom.
Entered as second.class matter in the New ~ork (N.Y.) Post Office.
EDITORIAL OFFICE :
COVENTRY.
PUBLISHING OFFICES :
20, TUDOR STREET, L'ONDON, E.C., ENGLAND.
CONTENTS. NOTES
PAGP. .. 893-894
USEFUL HINTS AND T1Ps : EQUAL StzE TYRES-THE SPARE CovER
-THE RlGHT WAY TO POUR PETROL (ILLUSTRATED) • •
895
THE N EW 35 H.P. TALBOT CAR (ILLUSTRATED)
THE R.A.C. AND M.U.
THE RELIABILITY OP THE H.T. MAGNETO
ONTHE ROAD. Bv Owrn ] OHN
A STUDY OF WIND SCREENS (ILLUSTRATED) • •
As OTHERS SEE Us
.. 896-897
898
898
899
, • 900-903
903
THE CERTUS FRICTION DRlVE CAR (ILLUSTRATED) • •
IN QUEST OF A C AR : SO!\IE CRITICISMS OF OLYMPIA..
904
• • 905-908
CoNTlNENTAL NOTES AND NEWS..
THE 22 H.P. S.C.A.T. C AR (ILLUSTRATED)
CoRRESPONDESCE • ,
909
910
·, 9II-915
THE RELATION BETWEEN POWER AND SPARK ( ILLUSTRATED) .• 916~920
FLASHES
THE FOUR INCH RACE-THE R.A.C. DUST TRIALS, 1907 . .
THE STANLEY SHOW
A Two-PURPOSE HooD (ILLUSTRAlED)
AN ADJUSTABL E PACKING PIECE (ILLUSTRATED)
R.A.C. OFFICIAL TEST-CLUB DOINGS . •
921
922
.. 923. 924
924
925
925
SOME QUERIES A:-lD R F.PLIE.: • •
926
"THE AUTOCAR" SUBSCRIPTION RATES: British Isles, 16s. Abroad (thin paper edition) 22". Sd. per annum.
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faotes. Accumulator or Magneto. The motor world received a shock last spring when Dr. Watson delivered his paper before the Royal Automobile Club and once and for all killed belief in the hitherto greatly respected "fat " spark. Dr. Watson 's method of investigation were so thorough as to be absolute ly convincing, and we were so impressed by them th at we asked him to make a similar series of comparisons between the power dtveloped by a petrol engine when fired by accumulator and coil and when fired by high tension magneto. This Dr. Watson has done, and on 916 and following pages he narrates the results of his experiments, and publishes indicator diagrams. These . are, so far as we are aware, th~ first series of scientific comparative exp"riments between accumulator and magneto which have been made. Previously experiments have been conducted, but they have not been carried right through with scientific accuracy, and, so far as we know, they have only dealt with th e maximum powers which could be obtained with one or other system . Before starting on his investigation, we p articularly requested Dr. Watson to investigate the behaviour of the engine when using a weak mixture and fired by accumulator or by magneto. We, like almost all other motorists, have long been convinced that with a magneto a weak mixture would fire with much greater regularity th an it would with the very best accumulator system, even when carried out in the most accurate manner and by means of high tension distributer and single coil. It will be seen that this roadside impression is thoroughly borne out by the experiments, and not rudely shattered by the cold light of science as was the old belief in the fat spark. In other words, although it is possible with the accumulator system to develop as high a maximum as with the magneto for all round running, the magneto produces superior results, as it will fire a weaker mixture regularly, and consequently it has in this sense a greater range and higher economy. Perhaps, however, the most important point accentuated by Dr. Watson's latest investigations is a fact that is too often lost sight of by designers. That is to say, we must not consider the spark at the plug alone, and in searching for the best results, the position of the sparking plug, th~culiarities of the carburetter, and the method ado ted to throttle th e engine must all be borne in mi d.
'.i\.mateur Owners' Requirements. Too many cars are designed without much consideration for the requirements of the amateur owner who looks after his car himself. It seems to be assumed that all cars will be looked after by a well-qualified paid driver, who will have ample time allowed him by his employer for the work, and, what is more, will be able to command the assistance of two or three men whenever he wants them. Every car should be made so that all adjustments and replenishments can be made singlehanded. To a la rge extent the question is one of accessibil:ty. The article on page 905 is written by an amateur owner who has ideas of his own. One or two of his statements we do not endorse, but in the main we a re entire ly in accord with his views.
For instance, the author of the article lays great stress upon being able to enter the driver 's seat from the right. This is unquestionably a convenience, but a car arranged in this way must either have its control levers more or less uncomfortably placed for driving or so arranged that it is very difficult to connect them simply to the gear box and brakes. At the same time, there are possibilities that a satisfactory compromise may be reached . There is really no very good reason why the levers should be placed on the right-hand side. They might be placed in the centre between the driver and his companion, as they are in the Linchester. Then, again , with a properly designed en~ine
