Comments by "Big Blue" (@bigblue6917) on "The Invention of the Depth Charge - Kaboom? Yes Jellicoe, Kaboom!" video.

@flaviosalatino8192 It was a development of the Blacker Bomber which led to the PIAT and also the Hedgehog so within the timescale.
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I have read that the spigoted mortar, which was the basis for the Hedgehog used in WW2, was used by the Germans as a trench mortar in WW1. Blacker, who came up with the Blacker Bomber spigoted mortar which led to the Hedgehog, may have known about the German spigoted mortar and if so then Germany was indirectly for the Axis submarine losses to the Hedgehog.
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