Text copied from TM9-1985-2 German Explosive Ordnance 1953 :

Description: Externally, the igniter consists of a cylindrical brown bakelite housing with a male thread at one end to take a deep bakelite arming cap. The other end bears a female thread into which a metallic percussion cap and detonator assembly is screwed. Internally, a glass ampoule containing the liquid chemical agent rests on a bakelite striker retaining disk so that approximately half the ampoule protrudes from the housing into the threaded arming cap.

The striker retaining disk rests on a narrow shoulder of the igniter housing ad has four deep holes that pass through it to the reaction chamber below. A partition in the igniter housing is positioned below the striker retaining disk, and with it, forms the enclosed reaction chamber. The spring loaded striker shaft is made of a special white metal and is fastened to the striker retaining disk by means of a small screw. The striker shaft passes through the reaction chamber and terminates in the striker head. Only a restricted portion of the striker shaft is exposed to corrosion within the reaction chamber. All other parts are carefully covered with rubber sealing washers to prevent the liquid agent from seeping out of the reaction chamber and coming into contact with other metal parts. The striker spring is compressed between the shoulders of the striker head and the housing partition. The percussion cap and detonator assembly is threaded to fit any standard German charge and is fitted with a rubber washer and transit cap. The delay periods have been calculated for the following temperatures: 68°F., 3to5¼days , 32°F., 21to31days , -31°F., 96to167days. The chemical reaction ceases below -40°F. but resumes as soon as temperature rises above that point.

Photo below © Joachim.

Operation: The threaded arming cap is removed and the glass ampoule is inserted into the igniter body, neck first, in order to insure complete drainage. The cap is then screwed on until a slight resistance is felt by its contact with the ampoule. A Sprengkapsel No.8 is placed in the percussion cap and detonator assembly and the igniter is screwed into the mine or charge. By turning down the threaded cap still further, the glass ampoule is broken and the liquid chemical agent trickles through the four seep holes of the striker retaining disk into the reaction chamber below. The igniter is now "functioning" but may be handled for a period of 5 hours. The chemical corrodes through the exposed portion of the striker shaft, releasing the spring loaded striker which fires the percussion cap, detonator booster and main charge.

Employment: This igniter is used for delayed action demolition.