Such a Durand motor sins only by the number of its parts, the inconvenience of which is noticeable not only by the amount of lubrication they require, but also by their rapid deterioration.

Daimler motor.—This motor, constructed by Panhard and Levassor, has become especially famous for its application to power-driven road vehicles. It gained nearly all the best prizes in the automobile races organised in 1894 between Paris and Rouen, and again in 1895 between Paris and Bordeaux. MM. Panhard and Levassor also construct their motors as fixed engines, but except for slight modifications, the mechanism is the same in both; we shall therefore describe the automobile type.

There are two single-acting cylinders working on the same crank-shaft. A central valve allows compressed air to be admitted which completely drives out the products of combustion. The admission and exhaust valves are enclosed in a chest also containing the incandescent tube which ignites the mixture. The governor on the crank-shaft prevents the exhaust gases from escaping when the normal speed is exceeded. The gases remaining in the cylinder prevent a fresh charge from entering, and during the next revolution no explosion takes place. The whole mechanism of the engine, together with the fly-wheels, are enclosed in an air-tight case communicating with the outside air by a valve opening inwards. The pistons during the backward stroke draw in air through this valve and compress it during the forward stroke; this forms the supply of compressed air for the explosive mixture. The carburetted air is obtained by the suction of heated air through oil placed in a vaporizing vessel. The motor cylinder is kept cool by a stream of water, which is itself cooled by travelling through a long annular pipe which runs completely round the carriage. The heat which it has absorbed from the cylinder is rapidly extracted from it by the circulation of the air on both the inside and outside of the tube.

Brouhot gas and carburetted air engine.—The firm of Brouhot of Vierzon construct an engine capable of working either by coal, gas, or petroleum, and which has been especially designed for agricultural operations. The general appearance of the engine is of the usual type; the cylinder projects over the bed-plate and is cooled by a water jacket. The explosive mixture is ignited by an electric spark produced from a battery of cells whose charge lasts from 120 to 130 hours, or by a small magneto machine driven by the motor itself. When working with petroleum a carburator is attached filled with a very volatile mineral spirit. The air is carburetted by being sucked through it directly into the cylinder. A second vessel is provided, which serves as a reservoir for oil feeding the carburator automatically, and keeping the oil in it at a constant level. The whole machine, though not presenting any novel features, is strongly constructed and thoroughly suitable for the work it has to perform.

Carburetted air motors for horseless carriages.—Although not to such a great extent in England, self-propelled vehicles have within the last two years come rapidly into favour on the Continent, and the success which has attended them has caused inventors and makers to concentrate their efforts on building the motors as light and as practicable as possible, as much for purposes of locomotion as for a host of other uses. We have already spoken of the Daimler motor, which is used to drive several different types of motor cars; we will now speak of more recent developments in the same direction. Among many of the same character, the most noticeable is the high-speed motor of MM. de Dion and Bouton, who have applied them with great success to the propulsion of tricycles (Fig. 28).

Fig. 28.—De Dion Motor Tricycle.

The cooling is effected by radiating cast-iron ribs offering a considerable surface to the air. The ignition is obtained by an induction coil and accumulator with a contact mechanism, invented by Captain de Place. The rotation of the crank-shaft is transmitted to the wheel-shaft of the tricycle by a reduction gear.

Among other motors we must mention the benzoline engines for self-propelled vehicles of Lepape, Gautier, the Gladiateur tricycles and quadricycles constructed by the Société des Voitures sans Chevaux; also the exceedingly light motors of the Kane-Pennington type; and lastly, the voiturette-tandem of M. Leon Bollée, some of whose vehicles have shown a remarkable speed with a very small consumption of fuel.

A few monstrosities have also appeared in the shape of a five-cylinder motor driving a bicycle called the “bicyclette Soleil Millet,” and a heavy and complicated mechanism by Wolfmüller, also driving a bicycle and using petroleum. These motors have not, however, obtained any success, nor will they at a future date, by reason of their complication and weight. It is almost unnecessary to state, that any of the above types may be equally well used for driving a dynamo and producing electric energy or light.