And then, on May 9, 1918, came a cablegram from the American Expeditionary Forces that brought the entire effort to an abrupt halt. The officers of the American Expeditionary Forces in no uncertain terms condemned the American defensive grenade. The trouble was that in our anxiety to protect the American soldier we had designed a grenade that was too safe. The firing mechanism was too complicated. In the operation required to touch off the fuse five movements were necessary on the part of the soldier, and in this the psychology of a man in battle had not been taken sufficiently into consideration. The well-known story of the negro soldier who, in practice, threw his grenade too soon because he could feel it "swelling" in his hand, applies to most soldiers in battle. In using the new grenade the American soldier would not go through the operations required to fire its fuse. Cases came to light, too, showing that in the excitement of battle the American soldier forgot to release the safety device, thus giving the German an opportunity to hurl back the unexploded grenade. As the result of this discovery all production was stopped in the United States and the ordnance engineers began redesigning the weapon. The incident meant that 15,000,000 rough castings of grenade bodies, 3,500,000 assembled but empty grenades and 1,000,000 loaded grenades had to be salvaged, and that on July 1, 1918, the production of live fragmentation grenades in this country was represented by the figure zero. Some of the machinery used in the production of the faulty grenades was useless and had to be replaced by new, while the trained forces which had reached quantity production in April had to be disbanded or transferred to other work while the design was being changed. By August 1 the new design had been developed on paper and much of the new machinery required had been produced and installed in the plants, which were ready to go ahead immediately with the production. It is a tribute to the patriotism of the manufacturers who lost time and money by this change that little complaint was heard from them by the Government. In the production of hand grenades the most difficult element of manufacture and the item that might have held up the delivery of completed mechanisms was the Bouchon assembly. There was an abundant foundry capacity in the United States for the production of gray-iron castings for grenade bodies, and so this part of the program gave no anxiety. The Bouchon assembly threatened to be the choke point. In order to assure the success of defensive-grenade production, the Precision Castings Co. of Syracuse, N. Y., and the Doehler Die Castings Co. of Toledo, Ohio, and Brooklyn, N. Y., worked their plants 24 hours a day until they had built up a reserve of Bouchons and screw plugs and removed all anxiety from that source. The total production of Bouchons eventually reached the figure 64,600,000.