Province on Kyushu, newly built for the sole purpose of housing the invasion forces and the reserves. None of the original structures remain, but the castle's ruined foundations survive in the formerly separate town of Chinzei, now part of the city of Karatsu in Saga Prefecture. The first invasion consisted of nine divisions totaling 158,800 men, of which the last two of 21,500 were stationed as reserves on Tsushima Island and Iki Island, respectively. The Japanese used a total of 320,000 troops throughout the entire war. On the other side, Joseon maintained only a few military units with no field army, and its defense depended heavily on the mobilization of the citizen soldiers in case of emergency. During the first invasion, Joseon deployed a total of 84,500 regular troops throughout, assisted by 22,000 irregular volunteers. Ming troops never numbered more than 60,000 troops in Korea at any point of the war. Over the course of the war, the Ming sent in total 166,700 troops, and also sent 17 million liang worth of silver and supplies to Korea (equivalent to about half a year of revenue for the Ming Empire). Weapons Since its introduction by the Portuguese traders on the island of Tanegashima in 1543, the arquebus had become widely used in Japan. While both Korea and China had also been introduced to firearms similar to the Portuguese arquebus, most were older models. The Korean soldiers' small arms were hand cannons with a simple mechanism and with either a gunstock or wooden shaft attached. After the Japanese diplomats presented the Korean court arquebuses as gifts, the Korean scholar-official Ryu Seong-ryong advocated the use of the new weapon, but the Korean court failed to realize its potency. In contrast, the Japanese often deployed the arquebus in combination with archery in war. During siege actions, Chinese deployed rattan shields and iron pavises (large shields), reputed to be musket-proof. The Chinese used a variety of weapons, including the Chinese long bow, swords,Swope. 2005. p. 38. firearms, early kinds of land mines, and early hand grenades. The Koreans also demonstrated massive use of hwacha – multiple rocket-propelled arrows, notably during the Siege of Pyongyang in January 1593. It had the ability to fire up to 200 singijeon, a type of rocket arrow, all at one time. The hwacha consisted of a two-wheeled cart carrying a board filled with holes into which the singijeon were inserted.