The Royal Society read another part of Letter L-168 about gunpowder explosions and cannon lengths

May 8, 1686

Birch, History, vol IV, p. 479, 28 April 1686 (O.S.) in London:

Part of a letter from Mr. LEEWENHOECK was read, containing his observations upon the figure of the parts of the nitre after the explosion of the gun-powder; with several curious remarks about the manner of firing gun-powder, about the quantity of air produced by the blast, and about the length of a cannon to carry farthest.