As an addition to the two arsenals, but as a subsidiary to the Frankford Arsenal, the Ordnance Department retained the 155-millimeter shell factory of the Symington-Anderson Company at Chicago and equipped it as an enormous stand-by shell factory with facilities for producing simultaneously 155-millimeter and 240-millimeter shell. This plant has been named the Chicago Storage Depot. Here was concentrated most of the special-purpose shell-making machinery acquired by the Ordnance Department during the war. It consists to-day of two departments. The active manufacturing department exists in ordinary, all machinery ready for immediate operation. In the storage department exists special machinery with a capacity for producing nearly 70,000 shell daily. This machinery is catalogued and assembled in factory layouts, virtually complete except for the ordinary commercial machinery used in the manufacturing processes, so that on short notice the Ordnance Department can ship from the depot shell-making units up to whatever capacity any future war contractor may wish to undertake. The installed equipment of the active manufacturing department has a daily capacity of 12,000 shell. In 1917 the shell-making capacity of the United States was small, and it was a year before facilities could be created and production started on a quantity basis. The reserve industrial equipment to-day gives us a daily manufacturing capacity of nearly 90,000 shell, a sufficient supply for a field army of 1,000,000 men until a new shell-making industry can come into existence.