This is a water-jacketed rocket motor made in 1932 or 1933 by members of the American Rocket Interplanetary Society (later called American Rocket Society). The motor was meant for ARS Rocket No. 2 but was left unfinished and abandoned because it was realized that water as a coolant would have been ineffective.
This object was donated to the Smithsonian in 1966 by the American Institute of Aeronautics and Astronautics.
Gift of the American Institute of Aeronautics and Astronautics