Opinions from Others.
Page 20
If you've noticed an error in this article please click here to report it so we can fix it.
The Editor inviles correspondence on all subjects connected with the use qj commenial 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 views expressed is accepted. In the case of experiences, names of towns or localities may be withheld.
Chars-a-banes and Excessive Speed.
The Editor, THE COMMERCIAL MOTOR.
[1565] Sir,—At the commencement, of another tourist and holiday season, I beg to draw attention to what I consider to be the excessive speed of certain motor chars-a-banes in North Wales.
I spent some days there at Whitsuntide and had one or two runs on public-service vehicles of this class. I am told they are in some cases geared as high as 25 miles per hour.
In the interests of the proprietors and passengers alike, it is to be deplored that no attempt is made to restrict the speed of these heavy vehicles running on solid tires. The roads in North Wales are extremely hilly and have many dangerous turnings and the high speed is simply courting disaster. It is to be regretted that the lessons to be learned from the last one or two serious accidents to publicservice vehicles last year have not evidently been appreciated properly. I trust the attention of owners may be called to this matter in your valuable columns.
—Yours faithfully, " ERIN." Glasgow, 6th June, Superheated-steam Consumption Figures.
The Editor, THE COMMERCIAL MOTOR.
[1566] Sir,—I was extremely interested to read in THE COMMERCIAL MOTOR of this week an account ot the trials of the new Garrett steam wagon. It may interest sonic of your readers to hear how these compare with some of the latest tests which we were enabled to carry out. with the Rutherford steam car, one of the few other successful examples of superheated-steam systems for use on common roads. The test in question was over a 50-mile run, and the car was driven without any special care. No attempt was made to free-wheel down hills, or to take other advantages of that kind. The average speed was 26 miles an hour throughout the run, and the final results, compared with those achieved during the recent Garrett test, were as follow :
Water consumed per gross ton-mile ... .84 lb. Paraffin consumed per gross ton-mile ... .34 lb.
Converting the fuel value of paraffin to that of coal, this last figure would give us the equivalent of .44 lb. per ton-mile. This result compares favourably with Garrett's .925 lb. per net ton-mile.
It must be remembered that our tests were carried out with an experimental machine which had many compromises and alterations embodied in it, and was over three years of age. With an exhaust steam turbine fan and a first-rate modern condenser, our water consumption could easily have been lowered to .44 lb. per ton-mile.
I would only add that the above figures include lighting up from cold. There is undoubtedly an enormous economy in the consumption when high pressure, in conjunction with a properly-designed superheated system, is employed. Garrett's deserve every credit for the persistence with which they have developed the superheater for road purposes. Its success is warranted through perseverance.—Yours faithfully, CHARLES A. Ross, A.M.I.Mech.E. Newbury, 8th June, 1912.
The Engine as a Brake.
The Editor, THE COMMERCIAL MOTOR.
[15671 Sir. In the North there have been several prosecutions recently of owners of steam motorwagons on account of their wagons not being. in I he strict legal sense, fitted with two independent brakes. Some authorities have objected to the reversing gear of the engine being reckoned as a brake, and yet it is the most efficient in use and the most frequent. It is quite an easy matter to pull a wagon going at the legal limit to a dead stand within its own length with the reversing gear alone so that any contention that it is not an efficient brae is quite out of the question. I submit, Sir, that the Act can never have intended that a brake so good should be disregarded and apparently these prosecutions are technical quibbles, brought to justify the existence of superfluous officials, and probably influenced by local road authorities who, knowing their roads are not up to requirements, are desirous of, so far as they can, restricting heavy motor traffic. or obtaining a plausible excuse for their own shortcomings. With regard to the road question, Mr. Twemlow, of liodens, Ltd. ably supports your leader in your issue
of the 23rd Ltd., in his letter (1560) published in your issue dated the 30th May, and it is hoped that it may have the desired effect. All users of motor transport must feel themselves indebted to you for the effort you are making to oppose the County_ Councils Association.—Yours faithfully, " VICTIM." Chequerbent, 3rd June.
Tramlines and Tire Wear.
The Editor, THE COMMERCIAL MOTOR.
[15681 Sir,—I enclose you a sketch of the tire that has run 7000 miles only. This tire is of a well-known first-class make, and was fittcd to one of the Cambridge mail-vans. U.W. 4 tons 1 cwt., B.A.W. 5 tons,
F.A.W. 2 tons 10 cwt., size of tire 1000 by 100 twin rear wheel.
This mail runs to and from Cambridge, making the up journey one night and the return journey the next. The cause of the undue wear can be traced to tramlines. It is an extraordinary thing that, although on this journey rather under onethird of the total mileage is on tramlines, the wear should take place in such a curious manner. All four tires on the rear wheels are so worn.
I have noticed this particular wear on other
Tram rail effect on vans running round Lon
tires, don, but nothing like that on the mails.
I have sent the section to Col. Crompton. It was cut. from a tire that was torn completely away from the steel band, and it shows curious signs of internal working in the hole through the middle of the section. This wear of course is accounted for in that the mail leaves London at midnight, when the stieets are free from traffic, and consequently for ease of running travels on the crown of the road, where the tramlines are. I have noticed further that the wear commences as in enclosed sketch, i.e., it appears to commence only at the outer end and gradually extending towards the centre, becomes deeper. I think this is a very important matter, which should receive the attention of the Road Board. No doubt you may be able to help us in giving it publicity in the " CM." The original section can be seen.—Yours faithfully, W. BAGNALL WILD.