At the Erie Howitzer Plant a similar procedure was followed. Here, on eleven acres of what had been vacant ground in August, 1917, the American Brake Shoe & Foundry Company six months later turned out finished 155-millimeter howitzers and reached a productive capacity of twelve howitzers daily before the armistice. The plant stands to-day as a complete gun factory, although all its equipment is greased and housed up, and its bays echo only to the steps of watchmen. While it was selected chiefly to be the stand-by plant for the production of 155-millimeter howitzers, at the shop has been concentrated the machinery and tooling used by the Northwestern Ordnance Company to produce 4.7-inch guns at its war plant at Madison, Wisconsin. This machinery had a capacity of four such guns daily. The howitzer shop and the gun shop occupy separate buildings. In the third building has been installed machinery for producing shell for 155-millimeter guns.
The machinery set up at Erie is designed to allow for increases in the powers of the two weapons to be made there. The howitzer can be increased in length (thereby increasing its range), and the 4.7-inch gun can be increased to 5 inches in caliber, without requiring fundamental changes in the machinery.
The present industrial position of the United States with respect to the manufacture of mobile field artillery may be seen in the following tabular summing up of the preceding paragraphs:
| Place of Manufacture | Type of Weapon | Monthly Production Capacity |
| Rochester Gun Plant | 75-millimeter gun | 360 |
| Watervliet Arsenal | 75-millimeter gun | 49 |
| Erie Howitzer Plant | 4.7-inch gun | 100 |
| Watervliet Arsenal | 4.7-inch gun | 17 |
| Erie Howitzer Plant | 155-millimeter howitzer | 200 |
| Watervliet Arsenal | 155-millimeter howitzer | 52 |
| Watervliet Arsenal | 155-millimeter gun | 60 |
| Watervliet Arsenal | 240-millimeter howitzer | 60 |
| Total monthly gunmaking capacity | 898 | |
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.
Meanwhile, be it remembered, the Rock Island Arsenal was working on 75-millimeter recuperators. It was decided to retain the recuperator department as an active branch of the arsenal. The arsenal was a little ahead of the Singer Company in the development, for it had actually produced an acceptable recuperator before the armistice; and it had 542 others in process in the shop. The arsenal’s production proper was therefore limited to this number, but the incomplete units from Elizabethport were later transferred to Rock Island, and the arsenal eventually completed 555 75-millimeter recuperators before closing down the department. These were pronounced to be in every way the equal of the French product.
The War Department provided no arsenal facilities for the production of recuperators for the 155-millimeter guns and howitzers, but centered its entire program for both mechanisms in the Dodge plant at Detroit. After the armistice it was first decided to retain the Dodge factory as a stand-by recuperator plant. All machinery and materials were protected against deterioration, and the plant, under guard, was added to the arsenal system, ranking as a subsidiary to the Rock Island Arsenal. Later the Dodge plant was sold, and nearly half of its machinery was moved to Rock Island.
The plan of artillery demobilization and industrial preparedness in this direction is now evident. Watertown Arsenal is the development center for the raw materials of artillery manufacture. Watervliet Arsenal, with its stand-by plants at Rochester and Erie, is the gun-producing center. Rock Island Arsenal is the center for gun carriages and recuperators.