r‘ ES Ili% I

Horse-power.

MY recent remarks on the subject of horse-power rating have aroused in me a certain interest in a subject which I have long tended to despise. I still think that it is a pity that the term horse-power has to be used. It is, after all, a scientific term with a definite meaning, and it is misleading to call a car a 10 h.p. when it actually develops 40 h.p. Far better to give the approximately correct figure, as do some makers, or else fall back on model names such as “Midget,” “Hornet,” ” Snipe ” and the rest of the animal tribe. The method of classifying engines by cubic capacity has the virtue of being international (except in America, where they wallow in cubic inches) ; but it is open to the criticism that, as an estimate of engine power, it ignores crankshaft speed. At present, nominal horse-power is decided either by the whim of the manufacturer, or by the famous R.A.C. rating. The latter, as I have attempted to point out, has, in my opinion, more virtue than is commonly ascribed to it. It fails lamentably however in the international field. For instance, the M.G. Midget, which passes for 8 h.p. on this basis, would be reduced to about 5 h.p. in France, and to 3 h.p. in Germany. The German formula, curiously enough, is, to my mind, the least scientific of the lot, being directly based on cubic capacity with 4 h.p. to 1 litre. The French formula, however, is imposing, as follows :— P=K u D2 LV

where P =the horsepower; K a coefficient of 0.00015 (in the case of 4 cylinder engines) and 0.00013 (in the case of multicylinder engines) ; u =the number of cylinders ; D =the bore in centimetres ; L =the stroke ; and V =the speed in revs, per second.

This formula is by way of being very scientific as it takes V into consideration. Unfortunately no one ever knows what V is, and even the French have to fall back on convention. Thus piston speed Is assumed, I believe, to be 6 metres per second, and an engine with a stroke of 120 mm. is assumed to rev. at 1,500 r.p.m. It seems to me that the R.A.C. formula reaches as accurate or inaccurate a result with considerably less trouble. However, attempts to apply something like the French formula are of long standing. I have in my possession a book published in 1909, which gives particulars of the cars of the period. In this case the author, in addition to giving the maker’s horse power, has calculated a figure for himself, on the assumption that 5,000 cubic inches suction per minute. 1 h.p. (The book was published in England, not in America ; we do advance, even here.) I presume that. this, or something like it, was the formula on which the early racing

cars were rated, the famous 70 h.p. Panhard et I,evassors and 60 h.p. Mercedes of undying memory. It is rather interesting to see how it works out for modern cars. Personally I cannot cope with cubic inches. However, assuming that 1 cubic inch .16.387 cubic centimetres, 5,000 cubic inches =81,935 cubic centimetres, or, let us say 82,000 cubic centimetres. On this basis a 1,000 c.c. engine running at 4,000 r.p.m. comes

out at about 24 h.p. A 3-litre engine running at 3,000 r.p.m. at about 55 h.p. The answers seem a trifle on the low side. Perhaps the difference between them and reality represent the progress of a quarter of a century.

Looking through my 1909 book I am struck by the number of marques which were once famous and which now are almost forgotten. For instance how many people now remember the Pipe, which represented Belgium in at least one GordonBennett race. In 1909 the Compagnie Beige de Construction Automobile were building a lovely engine with a hemispherical cylinder-head. The valves, at 45° to the vertical, were operated by pushrods and rockers from two camshafts in the crankcase. Who remembers that the Isotta Fraschini was called the F.A.I.F. ? Incidentally the habit of calling Italian cars by initials, once so popular, now seems to be disappearing. People will soon forget that Fiat is not a word. The S.C.A.T became the Ceirano ; the S.P.A. has disappeared.

Oh! Mors, victor of Paris-Berlin, where are you to-day ? But for that taxi which stands by Maidenhead Bridge, we would be in danger of forgetting even you ! I am afraid that most of us have forgotten the Zust. Yet I have read a book describing a journey round the world, in about 1910, in one of these Italian cars. It is rather literally translated from the Italian, which makes it all sound very melodramatic.

Bugatti on Rails.

This month’s piece of Bugatti news belongs to the present rather than the past, and comes from a correspondent who sends me a cutting from ” l’.Auto ” dealing with the latest Bugatti rail car. Incidentally the English railways, who are chronically chided for their failure to keep abreast of the times, seem to be living up to their reputation in the small attention

they are paying to high-speed petrol rail cars. Alas ! the poor steam engine ! Could M. Serpollet and the Comte de Lion ever have foreseen that the petrol engine which competed with their steamers on the road, might one day compete with the steam locomotive on the railway ! Admittedly French trains as a whole go much more slowly than English, but if present experiments are successful it will soon be possible to travel faster on French railways than almost anywhere else on earth. The Michelin pneumatic tyred rail car fitted with a Boulogne-type HispanoSuiza engine has already put up some pretty high speeds. Now, however, Ettore Bugatti has built a real fast rail car. It is mounted on two bogies, each having eight wheels, of which four are drivers and the other four act as guiders to keep the machine on the rails. Each bogie is driven by two Gold-Bug type eight cylinder engines of 120 x 130 mm. (12,760 c.c.), the total capacity of the power plant thus amounting to 51,040 c.c. This must be one of the largest recorded installations, although I think the White Triplex, with which Keech broke the speed record in 1928 had three Liberty engines giving a total of about 81,000 c.c. According to ” l’Auto ” each Bugatti engine develops 250 h.p. This seems rather little as a 2.3 Bugatti engine must develop nearly as much, but I am sure Charles Faroux is right. In this case the total power available is of course considerably less than that of recent record breakers. Nevertheless the Bugatti rail-car can, and does, get along at 120 m.p.h. According to my correspondent, tests are being carried out near le Mans, and both Ettore and Jean Bugatti are so thrilled that the railway officials cannot get them away from the controls, to have a try themselves. Meanwhile unfortunate representatives of the French Government cower helplessly in the “tonneau.”

The Isotta-Maybach. This same

This same correspondent tells me that he owned in 1909 one of the 1907 Kaiserpreis Isotta-Fraschinis. These cars had engines of 145.4 x 120 mm. and one of them, driven by Minoia, finished seventh in the German race. This machine, or one of the others of the team, was raced by my correspondent at Brooklands. After the War, the chassis was lengthened and fitted with a Maybach Zeppelin engine Most of my readers will remember the machine, which was raced until certainly less than ten years ago, first by Eldridge, then by le Champion. I must confess that the origin of the Isotta chassis has

always rather puzzled the, as the fact that it had been lengthened never occurred to me. The old car, or bits of it, must have had a racing life of nearly twenty years.

Early Alpine Motoring.

As I write, preparations for this year’s Alpine Trial are in full swing. Competitors, however, as they roar up the Stelvio in record time, might be amused to think, if they had tithe, of the terror with which the high passes were regarded in the early days of motoring. Vet an intrepid private owner, Comte Cognard, made the first passage in a car of a major Alpine pass— the St. Gothard—nearly forty years ago, in 1895. The car was a 3 h.p. Peugeot, fitted with one of the original type i)aimler motors, mounted at the back, driving forward to the gear-box, and thence back again by side chains. The engine cooling water circulated through the tubular chassis, and the car was steered by a bicycle type handle-bar. With this machine the intrepid Count set off, and all went well until fairly near the summit, when, with the gallant little motor pulling stoutly round the final hairpins, the party met a mounted Swiss soldier descending the Pass. The horse decided that motor cars were not to be expected near the summit of the St. Gothard, and showed his displeasure accordingly. The latter was „communicated, with interest, to its ,

rider, who as soon as he had regained eontrol of the situation, proceeded to pour forth a flood of invective at the unfortunate motorists. The Swiss have never been very fond of motor cars, and even after letting off steam in this manner, the soldier was not appeased. He declared that he was going to go and ring up the next village to give instructions for a fine (une amende) to be levied on the unfortunate Comte Cognard. He departed on his errand, but in these days it was not so easy as all that to hear on the telephone. Besides the post-master of .Aviola was also a hotel-keeper. So he may have had special reasons for a display of temporary deafness. At any rate when Comte Cognard and the Peugeot arrived triumphantly in Aviola, the post-masterhotel-keeper hurried up and informed him that he had received the instructions by telephone to reserve rooms (chambres) for the motorists, and they would find everything in readiness for them !

In justice to the Swiss it must be mentioned that by some the Count’s performance was treated more with that respect which it deserved than it had been by the cavalryman. The motorist in fact was presented with testimonials by the mayors and corporations of ..A.viola, Domo d’Ossola, Brigue and Andermatt. The , 1 ars t ;named read as folloWs

” We, the undersigned, solethnIy testify that M. le Comte and Madame hi Comtesse de Cognard, with a mechailician, iiore than 75 kilo S of luggage, and a’ Watchdog (!) were able to cross the St. Gothard in their Peugeot petrol car, without any assistance other than that afforded by the motor of the quadricycle.

A.ndermatt, 18th August, 1895.”

Flemish Problems.

Having recently returned from Northern Belgium I am feeling rather sore about the language problem which exists in that part of the world. Anyone who. rakes their car abroad comes up against this problem more or less acutely, but I had always imagined that French would take one through Belgium nicely. However in and around Antwerp if one asks the way of an ordinary wayfarer in French, one is greeted either by a stony stare or a flood of Flemish. The obvious solution would be, you say, to learn Flemish. I can, however, easily convince you of your error. In about the year 1900 the Flemish set about devising a word for a motor car, which they• conceived as a ” vehicle with a petrol motor going fast without horses or rails.” The word is as follows :—

S NEL PAARD EL OS Z ONDE RSPOORWEGPETROOBRIZTRUG.