of the front of the superstructure there was room for a gun; to the left of it the driver was to be seated. Almost all available space was then occupied; this was solved by letting the gun loader sit on the floor, with his outstretched legs below the gun breech. In this cramped position he was supposed to load the weapon, taking with his right hand rounds from a stock of 107 shells, that had been positioned on the left back of the hull, where in the standard AMR 33 the back exit hatch was located. The third crew member, the commander, sat on the right, squeezed between the hull roof and the engine; he had hardly any headroom. The Puteaux workshop only finished the prototype, now named the Engin P, in the Spring of 1935. After the gun was placed, the Engin P weighed 4565 kilogrammes and had a maximum speed of 54.1 km/h. On 18 April 1935 the CEMAV (Commission d'Expériences du Matériel Automobile de Vincennes), after testing, expressed a very negative opinion: "An ancient and outdated model [...] incapable of rendering serious service". Moreover, on 24 June the Conseil Consultatif de l'Armement decided that in future all guns up to a calibre of 47 mm would have to be towed by the Renault UE after modifying the latter type (though this in fact never happened). As a result, the Engin P was rejected. Renault YI In the years 1932 and 1933 Renault developed a series of three unarmoured military caterpillar tractors. The smallest of these, the tracteur de 2 tonnes with the factory designation Renault YI, largely used the AMR 33 suspension, though the sprocket was not spoked but consisted of a single convex plate. The vehicle had an open cargo room behind, the engine in front and the cabin in between. The French Ministry of War ordered two Renault YI. The Trench-Jumper AMR 33 prototype N° 78758 was used in 1935 by the engineer Nicolas Straussler, a former citizen of Austria-Hungary who at the time lived in the United Kingdom, to demonstrate his hydraulic "Trench-Jumper" that he already had tested in England. He had proposed the system in 1933 to the French Army and the Atelier et Chantier de la Loire had obtained an exemplar. The contraption consisted of two large hydraulic arms that were to be fitted on the front and back of a vehicle.