(5) The capacity of all projectiles received, unlimited by boosters, varied during the same period from 125 to 450 tons per week.
(6) The maximum capacity corresponding to boosters received was less than 100 tons per week.
In these facts it will be seen that the numbers of empty shell delivered to the plant was far less than the number required to accommodate the gas production. Many of the shell received were without boosters and therefore without value until boosters were provided, so that the limiting factor was really the supply of boosters. The booster supply was sufficient to take care of only a relatively small fraction of the toxic gas actually produced. The filling capacity of the plant was also in excess of the delivery of shell and boosters. The 75-millimeter shell-filling plant had a capacity of 1,200,000 shell per month, eventually double that, while delivery of shell was slightly over 300,000 per month and of boosters less than 200,000.
Because of the nature of toxic gas it is impossible to store it up in any large quantities. Early in the summer of 1918 large amounts were shipped in bulk overseas and there loaded into shell. Later we received instructions to stop all shipments in bulk except a limited amount of chlorine, and thereafter our production was limited to the number of shell and boosters available.
In June, 1918, we shipped in bulk 15 tons of mustard gas, 705 tons of chlorpicrin, and 48 tons of phosgene. This was to be exchanged for gas shell produced by the French. In late July the French had no more extra shell to be filled with American gas and this fact terminated the arrangement. However, we sold excess gas both to England and to France. England received 900 tons of our chlorpicrin and 368 tons of American phosgene. France took 300 tons of chlorpicrin and 1,408 tons of chlorine, equivalent to 1,226 tons of phosgene, since phosgene is 80 per cent chlorine including allowance for wastage in manufacture. France furnished phosgene shell to us in exchange for chlorine. In addition 200 tons of mustard gas were shipped to England and utilized by the English.
We therefore shipped to Europe in bulk 3,662 tons of gas or its equivalent, which gas was largely loaded in shell and used by the United States troops or those of the allies. This quantity was sufficient to load 1,600,000 shell, two-thirds of them being of the 75-millimeter caliber and the other one-third 155-millimeter, the total number being thought to be at least equal to the total number of gas shell fired by American troops in action. Thus while American gas was not actually fired in American shell against the Germans, American gas was used against the enemy and America furnished at least as much gas as she fired.
In addition to this we shipped 18,600 Livens drums loaded with phosgene. These contained 279 tons of gas, and some of them were fired at the enemy. We began producing loaded gas shell in the summer of 1918 and by August 9 had shipped 75,000 loaded 75-millimeter shell. These shell were unassembled for firing in the guns, the Ordnance Department having decided in June to assemble gas shell in their cartridge cases in France.
The Chemical Warfare production organization developed and manufactured a large number of special containers for the shipment of toxic gases. These were of special construction in order to guard against dangers that would result from leaks, and all had to stand the tests required by the Bureau of Explosives before they would be received for railroad shipment. The 1-ton containers, all of which would hold 1 ton of liquid chlorine, were designed by the Ordnance Department and would withstand a pressure of 500 pounds per square inch. The 300-pound phosgene cylinders, designed by the Ordnance Department, were made to withstand a 500-pound hydrostatic pressure and a 250-pound air test.
We purchased standard 55-gallon acid drums and standard-pattern cylinders for holding 75 pounds of chlorine.
We constructed chlorine tank cars, each tank with a capacity of 15 tons and a strength that could withstand a pressure of 500 pounds to the square inch. We also designed a tank car originally for the shipment of chlorpicrin and later used it for shipping sulphur monochloride.