Letter, from John William Lubbock to Sir John Herschel Autograph letter signed by sender. Has been with Philip Melvill of the East India Co. discussing the printing of the observations. Would it be a good use of John Frederick William Herschel's photographic papers to take a reverse of William Parsons' (3rd Earl of Rosse) drawings of nebulae? Cannot obtain Nicolas Clement-Desormes's or John Sharpe's papers. Doubts if the mode of measuring latent heat hitherto used can be recommended for accuracy. 17 April 1845