Letter, from Henry Oldenburg to Gisli Thorlaksson, dated at London Thanks Thorlaksson for his replies to queries about Iceland (see EL/B2/19); lists queries which appear to have been answered by conjecture eg about the freezing of quicksilver, spirits of salts, soap-boilers lye, pure oils, the maximum penetration of frost into water; that Bartholin has been instructed to send materials necessary to conduct these experiments (see EL/O2/162) 6 March 1676