Hand cannons were invented in the Yuan Dynasty and used extensively during the Ming Dynasty. The structure is of relatively standard design, which typically consisted of three sections: the front chamber, the powder chamber, and the tailpiece. The front chamber was the longest section, measuring about two-thirds of the overall length. Gunpowder and a projectile were loaded from the muzzle into the powder chamber, which was rounded like a Chinese lantern. Once the cannon was charged, it was lit via a small touch hole in the wall of the powder chamber. The tailpiece has a trumpet-shaped socket that could be fitted with a wooden stock to facilitate handling by the gunner.