Several small accidents happened during the trial, for the machine could not be completely controlled, but it was considered on the whole to be fairly successful and worthy of further attention. The suggestion was made that provided it could be made more powerful, and its mechanism improved, it might be used to drag cannon into the field instead of using horses for that purpose. Consequently, Cugnot was ordered by the Duc de Choiseul, Minister of War, to proceed with the construction of an improved and more powerful machine. This vehicle, which was finished in 1770, cost twenty thousand livres. It was in two parts, a wagon and an engine. The wagon was carried on two wheels and had a seat for the steersman; the engine and boiler were supported on a single driving-wheel in front of the wagon. The two parts were united by a movable pin. A toothed quadrant, fixed on the framing of the fore part, was actuated by spur gearing on the upright steersman's shaft in close proximity to the seat, by means of which the conductor could cause the carriage to turn in either direction, at an angle of from fifteen to twenty degrees. In front was a round copper boiler, having a furnace inside, two small chimneys, two single-acting brass cylinders communicating with the boiler by the steam pipe, and other machinery. On each side of the driving-wheel, ratchet wheels were fixed, and as one of the pistons descended, the piston-rod drew a crank, the pawl of which, working into the ratchet-wheel, caused the driving-wheel to make a quarter of a revolution. By gearing, the same movement placed the piston on the other side in a position for making a stroke, and turned the four-way cock, so as to open the second cylinder to the steam and the first cylinder to the atmosphere. The second piston then descended, causing the leading wheel to make another quarter of a revolution, and restoring the first piston to its original position. In order to run the vehicle backwards, the pawl was made to act on the upper side, changing the position of the spring which pressed upon it; then, when the engine was started, the pawl caused the driving-wheel to turn a quarter of a revolution in the opposite direction with every stroke of the piston. This machine was first tried in 1770 in the presence of a distinguished assembly, that included the Duc de Choiseul; General Gribeauval, First Inspector-General of Artillery; the Compte de Saxe, and others. Subsequently, other trials of it were made, with satisfactory results generally. The heavy over-balancing weight of the engine and boiler in front rendered it difficult to control. On one of its trips it ran into a wall in turning a corner and was partly wrecked. Further experiments with it were abandoned, and in 1800 it was deposited in the Conservatoire des Arts et Metier, Paris, where it still remains.