It remains for us to introduce our readers to the incredible progress made in France in mechanical engineering since the universal competition of 1851. As our compatriots can wait, without fear of losing anything but a little space in this review, we have observed the old laws of French chivalry, and ceded the first chapters to foreign peoples, if, however, we must consider the Luxembourgers and Belgians as being more foreign to us than the Algerians.
Dr. Warnier has spoken at length about Algeria, whose exposition precedes that of continental France; after such a competent master, we shall not enter into further details.
The French colonies have sent curious collections of natural history, but we have already strayed too far from our subject to be able to speak of them; besides, M. Jules Duval has kept our readers informed of everything that might interest them on the subject of the exhibition of our colonial empire, which the learned writer knows so well. Our publication has given the fullest account of Group X and of small trades in general, and we have just published an article on machine tools, and we thus arrive at Class 53: General Mechanics.
Steam engines are numerous in class 53; we have noticed all systems, with one, two, three and four cylinders, with vertical, horizontal, inclined and oscillating cylinders*-. Almost all of these machines, very importantly, were rightly awarded medals, which proves that all French manufacturers are doing well today.
The gas machines are much less numerous, which can be explained, because at a price of 30 centimes per cubic metre, gas is much more expensive than steam. There are only three systems. Otto, Lenoir, Hugon; the first seems to us the most ingenious
ingenious, the second the most widespread; the last the most practical. In addition to the steam and gas engines, we still have the water pressure, compressed air, hot air and ammonia engines, which were almost unknown ten years ago, but are now being studied everywhere and are already used on many occasions.
We find a fine electric machine by Mr. Van Malderen, similar to those he supplied to the lighthouse administration. The English have exhibited several electromagnetic machines, but that of the Birmingham Company is only a counterfeit of the Alliance machine (of which Mr. Malderen is the foreman) and its light has neither the power nor the regularity of that of the French machine. Messrs. Wilde and Ladd have invented machines based on different principles which are, from the theoretical point of view, real marvels, but from the industrial point of view, the necessity of making them rotate with a speed of two to three thousand revolutions per minute, restricts their use.
But from an industrial point of view, the need to make them rotate at a speed of two or three thousand revolutions per minute, singularly restricts their use, whereas the Alliance machine, making only four hundred revolutions, is within the ordinary rules of speed and achieves in the best possible conditions the transformation of motion into light.
Mr. Taurines won the gold medal for his spring dynamometers and scales. It is true that these dynamometers, intended to measure
These dynamometers, intended to measure the force of a shaft, are extremely ingenious, but we confess to preferring the vulgar scale to its spring balance; there always remains a doubt for the mind on the exactitude of the divisions traced on the dial where a mobile needle marks the weight.
We will arrive at the mining equipment after having passed through the bodywork about which we will say only a word. The jury, faithful to its system of giving the big awards to the big companies, awarded the omnibus administration a gold medal; did it want to reward the excellent service of the lines, in this case nothing better; but the jury only had to appreciate the merits of the omnibus car exhibited, and it did not deserve a bronze medal. The omnibuses of the provinces, of Le Havre, for example, look like master carriages next to those of Paris, not to mention the Swedish omnibus-salons. Ah! what we have to do to possess and even to know comfort!
Let us speak quickly of the railways, there, at least, the blood tax is only one passenger in five million; that is very little, it is too much, but, alas! the earth is not paradise.
Let us first recall one or two principles. The wheels of locomotives tend to slide on the rails, to slip, without dragging the trains; to prevent this effect from occurring, it is necessary to increase the friction, the adherence, by overloading the axles; but the total weight of the engine is distributed among all the axles and, if one makes the pistons act only on one, one will use only a part of the adherence. If, on the other hand, several axles are coupled, the total bearing point is increased and a greater tractive force is available. Example: to pull a convoy at a certain speed, a force of one thousand kilos is required. One of the axles of the machine is so loaded that if an effort of 200, 300 kilos is exerted, the wheel will not slip; but if the effort is more than 500 kilos, the wheel will slip, so the convoy will not move; the second axle is in the same conditions, the wheels only slip under an effort of more than 500 kilos, so if the pistons act on both axles, they will be able to develop an effort of one thousand kilos, sufficient to make the convoy move. This is one of the essential conditions for the construction of locomotives; to be very heavy in order to be adherent; to couple as many axles as possible in order to use most of the adherence.
For high-speed locomotives, the wheels must also be very large, because the speed of travel is obviously proportional to the circumference of the driving wheels and to the number of revolutions they have to make, equal to the number of piston strokes. Corollary: in order to be able to give many piston strokes, one must have boilers that provide a lot of steam.
Few classes have received as many gold medals as that of railway equipment; indeed, in all countries, the construction of locomotives and wagons has reached a great degree of perfection. Our exhibition in particular is distinguished by this double character: our locomotives are the most beautiful of the Exhibition and our passenger carriages are about the most imperfect. There is, however, an exception to be made in favour of the large closed double-decker wagon which, in its two floors, has 78 seats. The Eastern Company only introduces this car for local roads, but the future probably holds higher destinies for it. To finish with the wagons, it is again the East which exhibits the van fitted with the Achard electric brake which received a derisory bronze medal. In this system, the adoption of which would have prevented all the recent accidents, the acquired force of the vehicle is opposed to itself and used to apply the brakes automatically as soon as the electric current brings the mechanism into play.
Finally, as a locomotive, the East exhibited a machine built at the Graffenstaden factory, in a system borrowed from the Germans, and which consists of coupling together not only the wheels of the locomotive, but even those of the tender; in this way, frightening loads are obtained, the pressure of which is entirely used for traction; this locomotive and its tender weigh 63,290 kilos.
The Orleans company exhibited two admirable locomotives; the first, the Cantal, is intended to pull freight trains on the line under construction from Murat to Aurillac, one of the most rugged on the French network. The machine, which weighs 60,630 kilograms, is supported on five axles, arranged to pass through short radius curves; to be able to climb the steepest ramps it needs a very high power, and consequently it consumes a lot of steam, so the heating surface is enormous. The tubular hearth consists of 280 tubes and its total surface area is 210 square metres.
The second engine is intended for express trains, which also have to climb steep inclines. It is known that Crampton machines are used for speed trains, which have two very large wheels at the rear as driving wheels; in this case the traction power is low. At last it was possible to make machines with two pairs of large wheels coupled together, and with double the power. The locomotive of the Orleans makes, in mountains, 70 kilometres per hour; the diameter of its wheels reaches 2m,20. These two very original machines were built to the plans of M. Forquenot, chief engineer.
The Lyon company exhibited another similar locomotive, also very beautiful, the Dalembert.
The Gouin company exhibited one of these Petiet locomotives, so excellent and of such a strange aspect. This formidable machine, rightly called the Titan, has twelve wheels, all coupled, set in motion by four cylinders; it is a backfire engine, that is to say that the products of combustion, after having passed from the rear to the front, return, by another bundle of tubes, from the front to the rear; this new group being above the other, the result is that the machine is so high that the chimney must be horizontal!
Foreign machines are generally less perfect, but almost all have a shelter for the mechanics, while only one or two French manufacturers have thought of humanity.
The illustrious English company Stephenson exhibited a locomotive with large driving wheels placed in the centre. The Germans still use four-wheeled machines quite often.
four-wheeled machines. Austria exhibited an Engerth locomotive with a tender with eight wheels coupled and connected to those of the machine, and in addition, two beautiful locomotives, coming out of the Sigl workshops and intended for the Russian railways; but the small Wurtemberg did better, it exhibited a locomotive, admirably understood for its special use, ordered by the Anglo-Indian railways.
In short, of the thirty-two locomotives exhibited by France, England, Germany, Belgium and the United States, nine-tenths are off the line. As for the railway carriages, they can be classified as follows. England: did not dare to exhibit any; Holland: mediocre; France: not much better; Switzerland: better; Belgium: good; Germany: very good. (We said in issue 10, all the good we think of it.) America has only models, they seem very good.
We have often spoken of public works in previous issues, so we will not return to them.
Let us pass without looking at the ship models, the agricultural machines of Cail, executed with a somewhat hopeless finish, the machines for engraving by electricity, the superb presses of Mr. Marinoni and so many skilled emulators, and finally the innumerable legion of crafts. Oh, how much there is to say!
We have saved one of our greatest industrialists for last, because his exhibition can be found everywhere.
The Honourable M. Gouin would seem, perhaps, to those who know his immense establishments, to have restricted his exhibition, if we judged him only by his Titan locomotive; but he has also brought the plans for this titanic viaduct bridge, eight hundred and twenty metres long, which he has just thrown over the Po at Mezzana Corti; But above all, Mr. Gouin can apply to himself the beautiful thought inscribed in St. Paul's in London, on the tombstone of his great architect, Christophe Wren, and say to the visitor, who wants to know the work of the blacksmith statesman: "If you are looking for the monument, look around you. "Mr. Gouin has exhibited the Exhibition Palace.
Every piece of writing needs a conclusion: in all conscience, here is the one inspired by this long study.
England is still the leader in the ever-increasing quantity of machinery manufactured, but in terms of beauty and improvement, she is often only behind France, North Germany and Belgium.
If awards were given to nations, we would give the first prize to France and the second to Belgium, which is still France, the free France.
©L'Exposition Universelle de 1867 Illustrée