Grenades hydrocyanic acid

Hydrocyanic Acid (Seison) Frangible Grenades were round glass bowls, 3.9 inches in diam contg 12.2 fl oz of Cu-stabilized ca 80% strong HCN aq soln which acts as a very storng systemic poison. There were two types differeing in minor details (Ref 2, pp 238—39 with Fig 181 Ref 1, p 201)... 

Fig. 2-38. A Japanese frangible hydrocyanic acid grenade, copper stabilized type. Photograph Chemical and Biological Defense Command Historical Research and Response Team, Aberdeen Proving Ground, Md.

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