The process can be repeated and, on introducing a new bullet into the barrel after each shot, it is possible to fire a certain number of rounds before having to compress more air.
The exemplar in the museum has the central part and the forearm in finely inlaid wood. The metal parts are finely engraved.
The compression chamber (length 31.5 cm) which is made of iron and was lined with leather, is in the shape of a truncated cone (diameters 8 and 4.6 cm) closed with a hemisphere in the widest part.
The barrel is iron; it is 79 cm long, the external diameter is 1.6 cm and the inside diameter is 1.1 cm.
The overall length of the gun is 116 cm.