Mortar shell

A mortar is a device that fires projectiles at low velocities and short ranges. The mortar has traditionally been used as a weapon to propel explosive mortar bombs in high-arcing ballistic trajectories. The weapon is typically muzzle-loading with a short, often smooth-bore barrel, generally less than 15 times its caliber. Modern mortars are light and easily portable. They can be used for close fire support with a variety of ammunition.

Mortars have been used for hundreds of years, originally in siege warfare. Many historians consider the first mortars to have been used at the 1453 siege of Constantinople by Mehmed the Conqueror. A European account of the 1456 siege of Belgrade by Giovanni da Tagliacozzo said that the Ottoman Turks used seven mortars that fired "stone shots one Italian mile high". The time of flight of these was apparently long enough that casualties could be avoided by posting observers to give warning of their trajectories. However, earlier mortars were used in Korea in a 1413 naval battle when Korean gunsmiths developed the Wan'gu (gourd-shaped mortar) (완구,碗口). The earliest version of the Wan'gu dates back to 1407. Choe Hae-san (최해산,崔海山) (1380–1443), the son of Choe Mu-seon (1325–1395), is generally credited with inventing the first Wan'gu.

Early mortars, such as the Pumhart von Steyr, were also large and heavy, and could not be easily transported. Simply made, these weapons were no more than iron bowls reminiscent of the kitchen and apothecary mortars whence they drew their name. An early transportable mortar was invented by Baron Menno van Coehoorn (Siege of Grave, 1673). This mortar fired an exploding shell, which had a fuse lit by the hot gases when fired. This innovation was quickly taken up, necessitating a new form of naval ship, the bomb vessel. Mortars played a significant role in the Venetian conquest of Morea and in the course of this campaign an ammunition store in the Parthenon was blown up (see diagram).

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