Engines as Brakes.
Page 3
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Use of "the Reverse" in a Steam Vehicle Again Held Legally Admissible.
An interesting case came before His Honour Judge Lindley, at New Mills (Derbyshire) County Court, on Monday last, this being the adjourned hearing of an action brought by one Joseph Stanway, a cab proprietor, of Buxton, against the _Basalt Roa,dstone Co., Ltd., of Mill Cliff, _8 uxton, for damages to his horse and landau through the alleged negligent driving of the defendant company's servant. Several other actions turned upon the result of this action, which was regarded as a test case. The original nearing, at the same court, took place on the rth lily last, when evidence was adduced to show that the defendant company's steam wagon, a Sentinel vehicle constructed by Ailey and MacLellan, Ltd., of volinadie, Glasgow, sideslipped in Terrace Road, Buxton, slewed round into the plaintiffs cab, and thereafter smashed through some railings. Evidence For the plaintiff was given to the effect that the vehicle was travelling at speeds variously estimated to reach 15 or 20 miles an hour, and much of it was of an amusing order. it was given in evidence that the road in question had been freely treated with calcium chloride, prior to the accident, and that at least one other motor vehicle had had a sintilar experience on the same hill, prior to the sideslip of the Sentinel vehicle in question. For the defence, evidence was given that the rate of travel was about three miles an hour, and that the vehicle had gone down other steeper gradients, with a load of five tons, on the day of the accident, in perfect safety, whereas it was unladen at the time of the sideslip. A traction-engine driver stated in evidence that the road " was like a ruas.a of wax, and slippery, and was brown in colour." Expert evidence was adduced to show that. the treatment of the road tended to make it greasy and slippery, as laid. The Judge held, on the occasion of the first hearing, that the sufficiency of the brakes had to be settled, the point haying been raised that a steam engine was not admissible as a second brake under the requirements of the Motor Car Use and Construction Order, which states that "The motorcar shall have two independent brakes in good working order, and of such efficiency that the application of either to the motorcar shall cause two of its wheels on the same axle to be so held that the wheels shall be effectually prevented front revolving, or shalt have the same effect in stopping the motorcar its if such wheels were so held."
.-Xt the hearing on Monday last,counsel for the plaintiff was Mr. Gilbert Jordan, instructed by _Messrs. Bennett and Co., of Chapel-en-le-Frith and Buxton, whilst counsel f or the defendant company was Dr. Atkinson, instructed by MOSSES. Bootc, Edgar and Co., of Manchester. Dr. Atkinson, at the opening of the court, addressed His Honour and gave a summary of the working of the Sentinel engine. He then called Mr. D. H. Simpson, the proof of whose evidence is quoted below_ I am a member of the Institution of Automobile Engineers, In 1902, 1 joined Alley and MacLellan, Ltd., as their ilesiguer and the present engine and brake fitted to thMr lorries are, still practically as I designed them, 1 manufactured motor lorries err itty own account for some years. `Fo-da-v. I mu head of the experimental departmeilt it 'Hans Renocd, Ltd.
" The Sentinel wagon differs from all other wil,ons in that the engine is never disconnected from the road wheels. The engine Is equally powerful forwards and backwards. An engine which is powerful enough to climb a hill is powerful enough I,, hold the vehicle down that hill, because the road resistance and urigine friction, IV Ii oiL are a-Zaalq tire ea;,ine going uphill. act as brakes downhill. It thus requires much less power IA) hold a vehicle downhill hart to drive it unhill. " The distinction between a petrol and steam engine, used as a brake, is that the petrol engine has only a certain amount of retarding effect, which is constant, and which may or may not be sufficient to stop the vehicle, whereas the retarding effect of a, steam engine so connected to the wheels that, it is capable of climbing any hill that the wheels can grip will be enough to bring the vehicle to rest while deicending the same hill, and if necessary to lock the wheels. • "This Sentinel brake is worked with the steam shut oft, and the medium used is compressed air. The brake has, therefore. MI connection with the propelling power. It is .:attficient to lock the wheels. The engine thereupon ceases to be is steam or propelling engine, being cut off from the boiler, and becomes at once a compressed-air brake only.
When going downhill, a partial brake is formed by shutting off the steam. pressing down the foot pedal and reversing the engine. This brake will be equal to the ()Gmpression of a petrol engine. To increase the retarding action to a point when the wheels will be locked, the foot pedal is lifted up. This prevents the air from leaving the engine, awl so the pistons will become jammed by the compressed air. ill I hi' oesi if my knowledge, every registering authority accepts this _form ■ if brake as meeting the law's requirements."
Mr. G-enrge W. Watson, A.M.I. Mech.E., Kinst.A.E., of the editorial staff of THE COMMERCIAL MoToa, was also called and sworn.
His Honour, in summing up the case, said he was not prepared to take the view that the road was in a dangerous condition due to the calcium chloride. The plaintiff had failed to establish negligence on the part of the driver, of his mate, or of the owners of the vehicle. He did not feel called upon to decide the point that the engine was an independent brake. but in his own mind he was quite clear that the engine of a steam-propelled vehicle was equally as good a brake as that on the differential of a petrol driven motorcar. He dismissed the action, with the usual order as to costs.
It should be noted that, in accordance with the reported proceedings of the C.M.U.A. General Committee on the 20t1t tilt. (see page 72 dente), the Association has kept in close touch with this case. Colonel Crompton and Mr. Sbrapnell Smith, owing to im perative engagements in to were unfortunately not able to be present, but the case, partly by reason of the correspondence with the Secretary of the C.M.1T.A., was one which it was felt must have a satisfactory termination. It should also be noted that, although the expert evidence was almost wholly directedpreying the unique braking qualities of the entinel engine, particularly in relation to its working sa,tisfactorily as an air compressor, independently of the steam, the Judge's views apply to all steam wagons. We !night also refer readers to a, case which was settled at the West London Police Court, in respect, of a steam wagon owned by Pickford's, Ltd., in 1904, when the reverse gear was also held to be equivalent to one brake. On the other hand, so far as regards a petrol-driven vehicle, the case of Wilmot versus SouthwelL in which it was sought to show that a petrol engine was efficient as an independent brake, failed, and the decision was upheld by the. Divisional Conti-, The situation, therefore, is t that any petrol engine whichi can be disconnected by a clutch from the transmission is not to be reckoned an independent ,brake, whereas a steam engine, generally speaking, is so to be reckoned, and most certainly in the special case of the Sentinel wagon. We should say that it will be extremely difficult, if not impossible, for any case to be sustained in which it is sought to show that a steam-propelled vehicle is not to be so classed, unless orn:t were to be produced in which an ordinary type of friction clutch were interposed between the crankshaft of the engine and the main transmission.