This is a model of the "self-moving and combustible egg" of the Syrian Al-Hassan er-Rammah and is believed to be the earliest known rocket propelled torpedo. Crude sketches and a description of it appear in Hassan's Arabic manuscript, The Book of Fighting on Horseback and with War Engines, completed in A.D. 1280.
It is not known if he ever built the device. The two pans connected together were filled with an incendiary mixture and the whole was propelled by two rockets. As the rockets were ignited, the device was aimed toward an enemy ship. When it struck, the enemy ship was to catch fire and be destroyed. The model was built especially for the National Air and Space Museum and donated to the Museum in 1976 by the George Marsden Design Company.