Letter, from John Forbes, D.D. to Sir John Herschel, dated at Glasgow Autograph letter signed by sender, with enclosure. Last year John Frederick William Herschel agreed to review John Forbes's paper [see John Forbes's 1847-3-13] and to forward it to R.S. L. if it is accurate. John Forbes now submits paper to John Frederick William Herschel. 17 April 1848