developed, along with gunpowder flamethrowers. Like firearms, cannon are a descendant of the fire-lance, a gunpowder-filled tube used as a flamethrower; shrapnel-like material was sometimes placed in the barrel so that it would fly out together with the flames. In due course, the proportion of saltpeter in the propellant was increased to increase its explosive power. To better withstand that explosive power, the paper and bamboo of which fire-lance barrels were originally made came to be replaced by metal. And to take full advantage of that power, the shrapnel came to be replaced by projectiles whose size and shape filled the barrel more closely. With this, we have the three basic features of the gun: a barrel made of metal, high-nitrate gunpowder, and a projectile which totally occludes the muzzle so that the powder charge exerts its full potential in propellant effect. Firearms remained in use in China throughout the following centuries. Meanwhile, gunpowder and firearms spread elsewhere very quickly. Gunpowder seems to have been widely known by the 13th century. The Europeans, Arabs, and Koreans all obtained firearms in the 14th century. The Turks, Iranians, and Indians all got firearms no later than the 15th century, in each case directly or indirectly from the Europeans. The Japanese did not acquire firearms until the 16th century, and then from the Portuguese rather than the Chinese. In 1326, the earliest known European picture of a gun appeared in a treatise entitled "Of the Majesty, Wisdom and Prudence of Kings". On February 11 of that same year, the Signoria of Florence appointed two officers to obtain canones de mettallo and ammunition for the town's defense. A reference from 1331 describes an attack mounted by two Germanic knights on Cividale del Friuli, using gunpowder weapons of some sort. Cannon were first used by the Muslims at Alicante in 1331, or Algeciras in 1343. The French raiding party that sacked and burned Southampton in 1338 brought with them a ribaudequin and 48 bolts (but only 3 pounds of gunpowder). The Battle of Crécy in 1346 was one of the first in Europe where cannons were used. However, early cannon were not very effective, the main benefits being psychological, frightening men and horses. Short barrelled, large-calibre "bombards" were used up until the late 15th century in Europe, during which period they grew increasingly larger. In the mid-15th century, mortars also appeared. Various smaller weapons also