These fine weapons, all but one of which were designed by the French, the builders of the finest field artillery known, and manufactured only in France before the war, would be useless without recuperators, the recoil-absorbing mechanisms which make modern quick firing possible. Along with the guns there came to us the designs for the four French hydropneumatic recuperators. The French hesitated in the beginning about giving us their recuperator plans--not because they did not desire us to have the best in artillery, but because they thought, with much justification, that we should never be able to build them in time to be of service in the World War, although it was possible that after the war, by long and determined effort, we might be able to train mechanics who could make them. Only the sudden termination of the war, however, kept American-built French recuperators from serving at the front, for every one was successfully produced in this country before the armistice, including a single specimen of the perplexing 75-millimeter recuperator. Three immense, specially equipped plants and two government arsenals produced them. Millions of dollars were spent in preparing to build French recuperators. The Singer Manufacturing Company built a great plant at Elizabethport, New Jersey, to make 75-millimeter recuperators. The Rock Island Arsenal equipped a new department to build this same mechanism. Dodge Brothers spent $11,000,000 on an immense plant at Detroit for the manufacture of the recuperators for 155-millimeter guns and howitzers, separate designs, and separate manufacturing propositions. The fourth type, the 240, was put in production at a plant equipped for the purpose at Chicago by the Otis Elevator Company. Only one of the mechanisms, the 155-millimeter howitzer recuperator, reached the stage of quantity production before the armistice. For the millions spent on the others the Government had only the experience and a quantity of forgings and semi-finished recuperators possessing only scrap value as they existed on the day of the armistice. Therefore the Ordnance Department did not stop this vital production at once after the armistice. The Singer Company was working on orders for 2,500 75-millimeter recuperators. Although it had not succeeded in turning out a single acceptable recuperator by November 11, 1918, its processes had been refined almost to the point where they could begin producing these beautiful pieces of metallic sculpture in quantity. The Willys-Overland Company had built about 300 carriages for the French 75 by the date of the armistice, and it was decided to allow the Singer Company to build recuperators for these carriages and an additional 450 as a reserve. Considerations of economy later held the Singer Company to a total production of 247 recuperators, resulting in a shortage as compared with the carriages.