Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The Type 10 Grenade (十年式手榴弾, Jyūnen-shiki Teryūdan?) was the first fragmentation hand grenade designed and deployed by the Imperial Japanese Army. After the Russo-Japanese War of 1904–1905, the Japanese army experimented with a variety of grenades; however, no design reached mass production. Japanese military observers in the European front of World War I noted the technical development and tactical application of hand grenades as infantry support weapons with considerable interest, and the Army Technical Bureau was tasked with a project to develop a grenade launcher that could be used in combination with the Type 38 rifle, the Japanese Army's standard infantry weapon. The project failed for a variety of reasons, including too small a bore, too long a gun barrel and difficulties with a propellant. The Technical Bureau then turned to a World War I-vintage German design for a small signal mortar, which was developed into the stand-alone Type 10 Grenade Discharger.