The Royal Society read part of Letter L-154 about oil of tartar, potash, and camphor

May 9, 1685

Birch, History, vol IV, p. 395, 29 April 1685 (O.S.) in London:

Part of a letter of Mr. LEEWENHOECK of January 23, 1684/5 was read, concerning the figures of oil of tartar per deliquium, of Muscovy pot-ashes, and of camphire.