Letter, from Robert Hunt to Sir John Herschel, dated at Devonport Autograph letter signed by sender. Was gratified to receive his memoir and to find many of his doubts corrected by John Frederick William Herschel's experiments. Hoped to enclose some sulphuretted papers but the chemicals went astray in the post. Intends to follow John Frederick William Herschel's example and precipitate a glass. 23 May 1840