" " 19TH, 1906

THE :AUTOCAR B Journal·publtabeb in tbe interests of tbe mecbanicall\? propelleb roab carriage.

EDITED BY H. WALTER STANER.

No. 552. VoL. XVI.]

SAT°U RDA Y, MAY 19TH, 1906.

[PRICE 3D.

THE AUTOCAR.

(Published Weekly.))

Re(istered as a newspaper for transmission 1n the United Kingdom.

Eatered as second-class matter at the New York (N.Y.) Post Office.

EDITORIAL OFFICE :

COVENTRY.

PUBLISHING OFFICES :

20, TUDOR STREET, LONDON, E.C., ENGLAND.

CONTENTS.

NOTES: SINGLE GEAR RUNS-THE MISUSE OF THE TOP GEAR-WHAT

PAGE

HAPPENS JN THE ENGINE- THE HEDGELAND AXLK

623-624

llSRFUL HINTS ANO TIPS : MAKESHIFTS ON TouR (illustrated) .. . 625 THR DE LA Bu1RE CARS (illustrated) 626-629 IN THR HOUSE OF COMMONS ... 626 MONTE CARLO TO LONDON (illustrated) ... 630-632 AN EASTER TouR (concluded) 633 ON THE ROAD. By Owen John ... 634 A&RONAUTICAL NOTES (illustrated) 635 AN h

-A NoVEL COMPETITION-THK. ENGLISHMAN A BROAD-THE COUPE o'OR- PREPARING THE CIRCUIT DE LA SARTHE 636-638 HILL CL,U,fBING EXTRAORDINARY... ... 638 A DtSAP~OINTING MOTOR· T RIP .-.. 639-640 T HE Tk.IAL OF THE HED9'ELAN D AXLE • • • i40 THI< SAN FRANCISCO EARTHQUAKE (illustrated) 6H-64Z THE SINGLE GEAR CAR TRIA~ . .'. 642 " MoToR CYCLES AND How T o MANAGE THEM " • • • 642 C ORRESPONDENCE : THE BRiaHTON MOTOR TRACK-IN PRAISE OF THE

A A.-A.C. OFFICIAL R EPAIRERS- INTERNAL COOLING-THE IRISH RELIABILITY TRIALS-CONSJDERAT& AND INCONSIDERATE MOTORISTS-SPXED OF MOTOR CARS-PALMER C ORD TYRES-NEW C ARSREPAIRERS-FORDING STREAMS-MOTOR C ARS IN J APAN-8ALANCJNG OF PETROL ENGINES - RUNNING COSTS-AUTOMOBILE ASSOCIATION PATROLS- SUMMARY OF CORRESPONDENCX 643-647 MOTORING IN A NDALUC!A (illustrated) ... 648-650 THE MoToR YACHT CLua HEADQUART&RS (illustrated ) .•. 650 F LASHES... 651-653 CLUB DOING<;: HEREFORDSHIRE A .C.-l >ERBY ANO Dr STRICT A.C.-

ROYAL NORTH OF lRELA 'lfD YACHr CLuB-E'isEx COUNTY A.C.WoLVERHAMPTON AND D1srRICT A.C.-MOTOR UNION'S VISIT TO BIRMINGHAM-WEST SURREY A.C. - BRITISH MOTOR. BOAT CLUBC LUB FIXTURES, ETC. ..• 65-4-655 SOME QUERIES AND REPLIES . • . 656

T7~•• ;:~:;:••oo > ~ M . ~ • • • • • •

"THE AUTOCAR " SUBSCRIPTION RATES :

Single Gear Runs. There have been a good many ' top gear runs, and now the latest performance of a petrol car has taken the fo rm of a thousand miles single gear run. We should like it to be clearly understood that this drive is only a demonstration of what can be done with a sufficiently powerful engine, the impulses being sufficiently sub-divided, and provided always that the car is fitted with a clutch which can be slipped as much as required. It is true that the performance has been accomplished for the first time cm a six-cylinder engine, but we have no reason to doubt that it could be done, but not quite so comfortably or so smoothly, on a fourcylinder engine of equal power and with a clutch which would stand even more slipping. The demonstration has shown what can be done with a very powerful; engine, but not what it is advisable to do )n e~ery day practice. The only advantage worth cons1denng of a. single gear instead of three, or prefe~ab_ly four,_ speeds• is that it is cheaper to make, but this 1s certamly not a point which appeals to those who can a~Q:rd to buy 60 h.p. cars. Besides that, any money which can 1: >e saved by the partial elimination of the gear box will very soon be lost in the extravagance in fuel consumption and clutch renewals, for although a clutch may stand a thousand miles of inordinate slipping, __ it is very certajn that it cannot put up with such abuse eonstantly.

We are speaking somewhat _strong!~ on t;he matt~, because it is one of those things which rrught easily mislead those who did not realise the enormous power of a six-cylinder engine of 5in. bore and 4in. stroke~ and they might be led to imagine ~hat because sue~ an engine could propel a car on a smgle gear, machmes of much more modest power ought to perform similarly .. They might just as well argue that, because Sandow can lift and sustain enormous weights, ever) man should'. take a walk every day wit a grand piano on h.is. head, to keep himself fit.

The Misuse of the op Gear. As a matter of fact, · there is at the moment a." great deal of misunderstanding among motorists generally about the proper use of the top speed of a car. Itis all very well to keep the top speed in gear so long, as the engine is not labouring, but directly it labours a lower gear should be put in. Yet we constantly see carskept on the top speed much ~oo long when hill-climl:ing. It J.S true that the car will crawl over the surp_1?1t of a hill without the gear being changed, but the engmeis beating slowly and every impulse is a jerk which, imposes a tremendous strain upon the whole mechanism• and tyres. Further, this higher gear actually does not drive the car so fast as would the next lower gear with, the engine ma½ing, say, 1,000 revolutions a minute. No, immediate injury may result, though crankshafts andl connecting rods have been bent in this way before now,. but it stands to sense that if this foolish practice ispersisted in the life of the engine, gear, and tyres will· be shortened , and repai rs, renewals, and adjustmentswill be required much earlier than they would had not! the top gear been abused. What happens in the Engine.

There is no question that this matter is not generally· realised. We may give a very good example of what· actually happens as shown by the Gibson _ indicator. With this indicator, when running fast and free upon , the level, the pressure registered on the gauge is only. from 1 0 to 20 lbs. above compression pressure. When, the resistance is increased by hill-climbing, it rapidly, goes up to some four times the pressure of compression;. but if the hill increases in severity and the gear is notr changed down sufficiently early the pressure rises to, over five times that of compression, and if the diar would register sufficiently high it would show an evenhigher pressure. If top gear drives are really re_quired, then the engine must have ·such a reserve of