The Improvement of Acceleration.
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The more one observes the conditions under which motoriuses work in the crowded streets of the Metropolis, the more does one realise the necessity for rapid and uniform acceleration. The lay reader must not contuse this demand for better acceleration with one for higher road speeds than 12 miles an hour, as it is only in respect of the quick attainment of a speed of, say, ten miles an hour, either after a stoppage or a slack, that we ask for more attention to this matter, both from manufacturers and engineers-in-charge. The important bearing of improved acceleration has been mentioned by us on several previous occasions, one of these being in our issue of the 21st February, iyo7. We are glad to know that a marked improvement has taken place since that date, but it is doubtful whether the petrol-propelled vehicle, with a leather-faced clutch and an ordinary box of step gears, will be able to equal its petrol-electric or hydraulic rivals unless special pains are taken to encourage inventors and makers to concentrate upon this problem of acceleration. Every precaution should be taken to keep down the mass, and to neutralise the stored energy, of the male clutchmember and of the shaft which carries it. Ingeniously-devised connections may be introduced, in order to ensure the opening up of the throttle without lag once the fresh pair of wheels are engaged by the driver, but we doubt if it is fully realised how the acceleration curve is both lowered and interrupted under existing conditions. The average acceleration for petrol-propelled omnibuses is not materially greater than one foot per second per second, whereas passengers can comfortably accommodate themselves to double that rate of acceleration, as has been frequently demonstrated by experiment under the conditions of electric-traction practice on rails. We believe that, when the days return for the placing of further orders in London, as they surely will before very long, buyers will pay principal heed to this vital matter of
acceleration, and we are therefore most happy to observe that the Executive Conunittee of the Commercial Motor Users' Association Has invited the Royal Automobile Club to conduct a series of acceleration tests for motorbuses. These tests, we hope, will bring together a number of competing systems of transmission, in which event they should prove most informative and convincing. Mr. Bernard Hopps, of the British Thomson-Houston Company, was amongst the first to make such comparative tests, and he was able to show that his company's petrol-electric vehicle can attain a speed of ten miles per hour in 71 seconds, and in so short a distance as 21 yards. That gentleman, no doubt, and such an eminent authority on the matter of acceleration tests as Professor Matlock, will be prepared, if it be decided to go forward with the competition in question, to put their experiences at the disposition of the R.A.C.
Desirable Special Uses, and the Equipment of Heavy Motorcars.
Regret that the motor is limited, on the one hand, to special uses, owing to its failure to compete with 'alternative methods of haulage,. or, as in the case of agriculture, other forms of power, finds its converse in many directions, for the special uses to which commercial motors can be put, in particular applications where they are beyond competition, are very numerous. A number of illustrated articles on the subject of the special use of commercial motors have appeared in different issues of this journal. We may quote, at random, their employment : for the conveyance of petroleum spirit, cartridges, gunpowder, high explosives, matches, and other so-called dangerous goods which are adversely classified by railway companies; for the conveyance of drums of cable, and the subsequent winding of the cable through the underground conduits in the laying of electric mains; for ordinary, mechanical, and illuminated advertising ; for the provision of power for well boring; for the conveyance of accumulators for the temporary supply of power on the occasion of extensive substitutions in the power house of a big Paris newspaper; as self-acting, hoisting gear for millers ; for the rapid transference of fish, fruit, and other perishable goods; as a rent saver, by enabling manufacturers to move from the centre of Landon to the suburbs, and to conduct their deliveries as expeditiously as when they were in a highly-rated area; for the transport and operation of portable lifting hoppers; for the rapid delivery of coal from under the shoots, either at collieries or stations, and either with or without side-tipping gear, compartmented or otherwise; for the conveyance of statues; for economical haulage in connection with isolated building contracts ; in place of light railways; in the conveyance of workmen and their tools, with a view to the saving of time; for running on snow, when all horse-drawn traffic has to be suspended; for newspaper distribution; for the transport of pianofortes; for the rapid discharge of repairs to the overhead equipment of electric-tramway systems ; in connection with breakdown organisation for public services, such as water supply; for electioneering .purposes; and for the haulage of timber. We believe there will be a great development of combination devices, whose .object is the utilising of the engine power to effect work externally to the wagon, and that this
will largely take the shape of labour-saving appliances. We know orders have not been placed owing to the assertion, atter proof that a wagon was capable of taking three times the load of a horse-drawn vehicle, that it was a physical impossibility for the carman to stand the strain of haadling three times the load during the day. The mere fitting of a jib crane, as, for example, to raise and lower casks of beer from a lorry to a cellar, is one answer of many which have occurred to us, for the elimination of hand labour is the principle which underlies the successful adoption of such appliances where loading and unloading should be expedited. We might pass, next, to the construction of a contractor's lorry, say, for the conveyance of bricks. Here, the fitting of a winding drum, which can be used to operate the winding gear between the wagon and a block and tackle at the top of the building, so as to avoid mere idling while the bricks are being off-loaded by hand, and to economise labour in the elevation of those bricks to a staging or scaffolding against the side of the building in course of erection, might well provide the clinch
ing argument with the buyer. So far as the taking of power from an extra countershaft with external pulley is concerned, we might fill pages with examples of useful application, one of the most interesting which we have recently illustrated being that of the Yorkshire wagon, with a circular saw, for the cutting up of wood fuel for use under the boiler of the same wag-on (Vol. VI, No, 140, page 245).
ln conclusion, and as a striking confirmation of our argument, the universal activity of the fire brigades of the world, in turning to account power which is provided by the heavy motorcar, should convince everybody that this line of development ought to be studied in every particular case. Even a later example is provided by the motorcab company whose ambulance lorry utilises the power of its engine to haul any disabled cab on to the platform. The deep-rooted idea of traction-engine builders, that they have done all that is necessary when they have fitted a winding drum to enable an engine to pull itself out of a bad place, or to haul the
trailer wagons up a hill when the surface does not provide sufficient adhesion for the whole of the train to go un at one time, must not obsess manufacturers of motor wagons and tractors.
Points about Obstruction.
It is our duty to warn owners and drivers of wagons and tractors, that a not inconsiderable volume of feeling exists in the country on the subject of the obstruction which such wagons and tractors unquestionably cause at times. The writer has frequently been impeded, both when driving in London and when motoring in narrow country roads, through the inability of the driver ahead to hear even a loud and raucous-sounding hooter, and through the absence of any " leak-out " man. We have in our possession records of convictions for obstruction of tramcar drivers, with accom
panying fines varying from.C2. to it having been held by the Stipendiary Magistrates before whom these cases were brought that the obstruction was wilful if a driver went out in charge of a heavy motorcar which made so much noise that he could not hear the audible warning of a tramcar gong. Now, where a driver has a mate with him, the second man should repeatedly look behind, whether in town or country, so as to ascertain that no following vehicle of a higher speed capacity is being impeded, unless the driver of such heavy motorcar is prepared to keep to the near-side of the road at all times, which is seldom the case, owing to the easier running on the crown of the road, and which action is not sufficient to prevent obstruction in certain instances. We would urge upon all who read these lines, that failure to conciliate other users of the highway can only bring about restrictive by-laws, and we do not want to see the day come round when every owner will he obliged, by statute or regulation, either to put a man at the hack of each trailing unit, or, alternatively, to provide something in the nature of a commuuication cord.
The Shows.
Cordingley's Show on Saturday next, and the Olympia Show a week to-morrow, will open their doors to all who are owners of heavy motorcars, and to others who are still merely students of commercial motoring. Manufacturers and agents, equally Of accessories, components, stores, and tires as of complete vehicles and tractors, are ready to show and to explain their latest productions, and our readers may rest assured that " THE COMMERCIAL MOTOR " show reports will focus the numerous exhibits in their right perspective.
We have, by special request, arranged to issue the balance of the 48-page booklets which were prepared by members of the staff of this journal in connection with the SeptemberOctober trials, The contents and object of that booklet, as will be remembered, embraced matter and illustrations which cannot fail to enable a lay visitor, or anybody lacking a knowledge of mechanics, to take an intelligent interest in the numerous types which might otherwise confuse him. Some 16,000 copies of this booklet were distributed, with care and discrimination, diming the trials, and in connection with the writer's recent lectures before Chambers of Commerce, so that only 4,000 copies remain for use in the manner now announced. No matter that this booklet contains seven maps of the route, and other analyses which were of peculiar use during the trials; pages 17 to 30, which were specially prepared to suppleinent the otherwise incomplete information about the routes, as contained in the R.A.C. official programme, may, now that interest in them has ceased, be ignored the other pages are still of value.
Agricultural Motors.
The manufacture and sale of agricultural motors is probably one section of the industry in which there is most room of allfor a development from the special to the general.. All commercial motors begin to attract attention by their application in rare cases, but no large trade can be done until use and observation have jointly indicated the faults of early models, and the directions where economic service can be rendered. We do not write this stricture of any singular type, as this experience has been inevitably common to all who have tackled the problem during the last half-dozen years, but we seriously question whether any so-called agricultural motor has yet established a considerable degree of conviction in the minds of men who are competent to gauge the future which lies before such machines. It is well known that our large manufacturers of agricultural implements, with the one notable exception provided at Gainsborough, let alone proprietors of steam ploughs, have not yet taken up the agricultural motor fitted with an internalcombustion engine, and it must be admitted that this hesitancy is, in reality, because they know their own businesses best. Farmers and growers state that they must have an agricultural motor which is suited for alternative use upon the land, along the highway, or as a portable engine. For tillage purposes, the motor will only do a certain class of work, and it is, in any case, too heavy for some and too light for others. It is still far from satisfactory on hills, and, when engaged on threshing jobs, not infrequently requires a large amount of " easing " in its work. We do not hold the opinion that the agricultural motor is either impracticable or useless, but we regard it as being, with one or two exceptions, in an embryonic and somewhat crude stage of development in relation to the forms which it must assume before wide adoption is merited. The Dominion of Canada probably offers, as was explained at length in the course of an article which appeared in our issue of the 29t11 March, 1906, one of the greatest fields in the world, owing to the necessity for rapid working, and, perhaps, the competition which is announced to take place at Winnipeg in July next may be the starting point of a series of competitive trials, by means of which the march of evolution will receive a much-needed impetus. Particulars of these trials will he found on page 37 of this issue.