Opinions from Others.
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The Editor invites correspondence on all subjects connected with the use of commercial motors. Letters should be on•one side of the paper only, and type-written by preference. The right of abbreviation is reserved, and no responsibility for the views expressed is accepted. In the case of experiences, names of towns or localities may be withheld.
Chain.-drive Gearboxes.
The Editor, THE COMMERCIAL MOTOR.
[1,159] Sir,—The principle of the chain-drive gearbox of the London General Omnibus Co. is not novel. In 1901, designed a gearbox to drive by chains, engagement being by claw clutches ; it was a three-speed gearbox with reverse. We built nearly 100 of these boxes, and they are, so far as I know, all running to-day, and they have stood up and behaved most wonderfully. The chains, of course, running in an oil bath, do not elongate, and the life seems to give prospect of very long one. I should imagine, for an omnibus drive, with Hans lienold type of chair!, it would be a type of gearbox difficult to beat.
I am sending you a blue print [Not reprodeced.—ED.] of the original drawing of this gearbox, as fitted to our old 12 h.p. cars; it was redesigned, however, in somewhere about 1903, when we fitted the same type of gearbox to our four-cylinder 1.5-20 h.p. cars. I know one of these tars that has been driven between 30,000 and 40,000 miles, and the gearbox has never had anything done to it; it is in perfectly-good condition now, and does not require repairing in any way.—Yours faithfully,
Lowestoft. M. linooKE.
The Editor, THE COMMERCIAL Moron,
[1,160] Sir,—I was interested to read in your current issue a letter from a correspondent in reference to chaindrive gearboxes, and, though I am not familiar personally with the details of the gearbox of the company in question, yet, having had occasion a little time back to go closely into the matter of chain-drive gearboxes. I feel the matter possesses a certain interest for me, and perhaps for others of your readers.
My company here introduced, some three years or more back, a reverse Fearbox for marine work, under my patent it) which there is not only a chain drive but also a direct drive on the ahead. I do not, think the claim would be limited to any particular ratio of gear, etc., but, as regards different chain, drives in the same gearbox, there is the well-known example mentioned in the letter. namely, Messrs. -Brooke's practice, whicli was even earlier than mme, but on rather-different lines. Quite recently 1 came across a. Brooke car with chain-drive gearbox, and, though it had seen a lot of use, there did not seem to be much difference in the slackness of the three different chains, one of which, namely, that on which most running had been, would--it might be thought—stretch more than the others. Messrs. Brooke, no doubt, could say more about this than I can, and the only point I would like to mention, from experience, is that of the size and strength of the chains.
In a general way, my experience shows that the actual power to be transmitted is only a portion of what has to be provided for in the chains, and anyone making a chaindrive gearbox has to provide for a heavy and serious snatch or jerk, which comes on the chain if the load is suddenly applied, so that, really. the chain, I find, has to be mud' stronger than a calculation based upon the power transmitted would suggest. When one comes to think of it, this is not unreasonable, because it is just as though two gear wheels were run with a slack of, say, double the space between the teeth, in which case there would be n. fruitful crop of broken teeth. In properly-meshing gear is-heels, of course, such a thing does not exist., and there is little or no slack, but„ with a chain drive, even if there be no sleek at first, there must be some in time, and my company's experience on this point is somewhat varied. since marine-motor installations with silent-chain drives have been done up to 45 h.p. at about 500 rpm., the chain transmitting power from the engine to the propeller shaft. As regards the chain drive in the gearbox itself,
my company has done some big work in this way, such as. a gear transmitting 120 li.p, at about 400 r.p.m., the size of the reverse-gear shafts being '3 in. diameter. Your correspondent seems to be somewhat alarmed at the prospect of anyone's obtaining a monopoly for the chain-drive gearbox with direct drive, but, in view of what has been mentioned above. I cannot think otherwise than that his fears are groundless. though I hope some other correspondents may be able to add information of interest to your readers.—Yours faithfully, HARRY PARSONS Southampton. 27th May, 1910.
Taxicab Fares and Finance : the Importance of Earnings Per Mile Run.
Editor, THE COMMERCIAL MOTOR.
[1,161] Sir.—Withie the last few weeks, the desirability of an alteration of taxicab fares in the Metropolis has come from the region of the vague " ought to be " into that of " practical politics," and it is perhaps not inappropriate to examine at some length the intention of the authors of the present. scale, the necessity for a change, and the best form in which to give it effect. It is doubtful if, in framing the present scale, much more was aimed at than giving the public a new means of conveyance at a price which defied grumbling. The actual experience of the last three years has shown that the expectations of the framers have not been realized. These undoubtedly were :
That the owners would get sixpence, and the driver twopence for each mile the cab travelled (vide Sir H. Norman's articles in " The Daily Mail," January and March, 1907, and others). There were other expectations as to returns per day, etc., etc., but the fundamental idea was then that the cabs could return sightpence a mile. Waste mileage was to be more than compensated for by " waiting " revenue.
In practice. even from the first, this has not been the Case; an average of sixpence seems now to be looked upon as general. driver after driver has been suspended for not obtaining it, and, as the numbers of cabs increased, so " waiting " earnings decreased ; waste mileage grew, and the total return became lower. Yet, while returns thus grew automatically less, expenses increased; the firms had, for instance, to bear the greater part of the petrol duty, and the whole of the enormous increase: in tire costs.
It might be noted, here, that in their eagerness to comntend a new article to the public the owners insisted on the mileage limit of the old Cab Act being ignored, drivers were required to take fares almost any distance without provision for the waste mileage, and loss of the cars and of the drivers' time which returning empty involved. In effect, during sunny winter months, the mileage return hovered between .10. and 6d., at which rate neither men nor masters could live. Masters worried for greater returns, men obtained illicitly monies which they could not, owing to the condition of the trade, earn straightforwardly; masters proclaimed that, owing to the roguery. of their servants, dividends were impossible ; men said, and say, that bad masters make bad servants the world Over. The 81. rate has thus proved itself equally unsatisfactory to owners, who find their cabs doing 60 to 70 miles to get a gross return of 25s., which can hardly cover running expenses, let alone management, interest, and—most important of all-lost time of cabs stopped by police and under repair. Just as the secret of managerial success must be good mileage, so the secret of works success is high percentage of vehicles in regular running. Unsatisfactory to owners, the position is equally so to tho drivers who, on a 25 per cent, basis, only get for their day's work 6s. to 8s., 45. to Cs. of which goes [Why so much En.] in necessary expenses. The horse-cab driver's chief source of income, the tips, has steadily diminished for the motorcah driver, since the pious expectation that wage-earnings will be so good as not to necessitate tipping was advertised to the public! Upon the whole, the public is no better pleased; the 8d. a mile run is cheap; the 8d. for every ten minutes of time is dear. Is it possible, then, after our three years of experience, to devise a better scale concomitantly with a better rate of pay for the drivers I venture to think that it can be done. Such a scale must bring a greater return per mile to the master, who is infinitely better off if he gets 20s, for his cab travelling 30 miles, than 30s. for his cab going 60. The public, after all, likes to feel that it is dealing fairly with its servants: there can be no hesitation in condemning at once a'50 per cent, increase, but it is not merely the opinion of the writer, but of everyone of experience he has consulted, that a rate of 10d. per mile, and of 2t..L per minute, or 2s. 61. per hour for wailing, would, with the driver receiving one-third [Again, why so much ?—ED.1 of the takings, come as near satisfaction all round as can be hoped for. Of the exact effect of this rate, and of the other corollaries to it., I hope, with the Editor's permission, to deal later.—Yours faithfully,
Highgate, N. J. E. DAviEs, Users' Experiences : Tarred Roads—Coke Supplies— Technical Prosecutions.
The Editor, THE COMMERCIAL MOTOR.
[1,162] Sir,—I have just analysed the returns of my machines for the past six months, up to the 30th April, and the results clearly show that the business has been of inferior quality during that period ; it takes a lot of real hard work nowadays to produce even the. mostmoderate profit. Trade, probably is on the upward grade, but it will be some time before orders will become steady and substantial, During the recent spell of warm weather, we have had an opportunity of testing some of the latest methods of tarring roads under summer conditions; where the tar is laid on too thickly, the roads are very difficult to get along on, as the wagons sink in the soft tar, and at the same time a considerable quantity adheres to the tires, which makes travelling very dangerous both on sett-paved and macadamised roads, We have come across instances where a judicious application of tar has apparently solved the road problem for all seasons of the year, and other cases where the roads are as bad to-day as they were, before they were repaired, only a year ago. Owing to the rapid increase in motor-wagon traffic, coke is becoming increasingly difficult to obtain, and, as incandescent lights are almost universally used now, the quality of the coke is deteriorating; at present, I am paying as much as 15s. per ton for gas coke, two-thirds of which is pure rubbish, and I am pleased to be able to obtain all I require at the price.
I notice, in your issue of the 26th May, that " A Lancashire Carrier " is protesting against the present attitude of the police towards heavy motors in Lancashire. I can assure him that the trouble he complains of is by no means limited to his own county, and 1 think it would be well if the principal owners of commercial motors were to endeavour to meet the authorities and to see whether some " give and take " could not be arranged with regard to
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the present source of trouble. Carrying s not an exact Science, and can never properly be treated as such while the conditions under which it is performed are so fluctuating. Above all, the main object to be obtained is the perfecting of the work by heavy motors, and this will not be accelerated by hampering the trade with the rigid enforcement of regulations which were made when the movement was still in its infancy. There is no doubt that, whilst the authorities have had the disadvantages of heavy motors carefully explained to them, they have not been as carefully schooled in the difficulties under which the work of heavy motors is often performed. In connection with the strictness with which we are tied down to exact weights by the police, I recently had a typical case brought to my notice: a carrier had accepted certain eased goods, in the belief -that the weight stated on the delivery note was gross weight, whereas it turned out, eventually the weight given was only the net weight of the contents of the goods, making a difference of about one ton, which was sufficient to cause the wagon to be overweight by 3 cwt. This is_a point which carriers will have to watch carefully. Should a carrier be fined for overweight in such a case, has he any proper power to come upon the consignees for damage through showing a wrong weight on a delivery note? Your advice, Mr. Editor, would be esteemed on this point. LWe should think he had, did he care to enforce it.—E.]
Our log sheet is as follows: earnings. L110; tannage, 325; mileage, 1,635; percentage of work done, 98; coke used, 15 tons; oil used—gear, 18 gallons; cylinder, 10 gallons.—Yours faithfully, " MOTOR-WAGON CARRIER."
Commercial-vehicle Design.
The Editor, THE COMMERCIAL MOTOR.
[1.163] Sir,—Your correspondent Mr. G. T. Cutbush has, I see, revived the argument on the above subject, and in reply I would like to say that I was simply looking back on the past experience in the motor trade when I dismissed the subject of placing the engine under the driver's seat in " too curt a way." Mr. Cutbush has, further, put forward some claims for the horizontal engine, but experience has taught designers, long ago, that the horizontal motor must be ruled out of court, in designing a commercial chassis where the advanced stage which the industry has reached, forces them to offer the best, simplest and most-suitable machine.—Yours faithfully,
Wimbledon. ARTHUR E, A. M. TURNER.
Electric Lighting by Dynamo.
The Editor, THE COMMERCIAL MOTOR. E1,164] Sir,—We notice a letter appearing in several of the motor papers, suggesting that manufacturers should provide proper accommodation—in the design of their new models—for driving a small dynamo for electrically lighting the vehicle, in the same way that provision is now made for the magneto. This, of course, is obvious, hut it remains to be seen whether the majority of the manufacturers will decide to make provision for this speciality in their engine designs voluntarily, or whether they will wait until they discover the pressure of public opinion forcing them to do 80.
There is no question whatever about electric lighting being the illumination of the future for car work. The many advantages which it possesses over all other forms of lighting are so pronounced, that with a proper design and simple form of generator, together with a simple wiring system, we venture to predict that it will speedily displace all other forms of lighting. Realizing this for some time past, we have been negotiating with, a few of the. leading manufacturers upon the subject, with the result that two of the largest and best-known manufacturing houses in this country have decided to make proper provision for the C.A.V. lighting dynamos upon all standard models for 1911, and we have every hope of similarly interesting other leading makers, and thus getting them to follow suit. —Yours faithfully,
Acton Vale, IV.
C. A. VANDERVELL AND CO.