New American floating mine developed according to the Dutch magazine Marineblad 1915-1916 no. 2

An item reported that the US artillery office developed a floating mine which full filled the demands of the Convention of The Hague meaning that one hour after they were dropped they automatically were switched off.(1) There were a hundred ordered to be used for tests.

Note
1. The Hague Convention VIII dated 18 October 1907dealing with the use of automatic submarine contact mines.