Letter, from Alexander Wight, Jr. to Sir John Herschel, dated at 6 Clarenden Terrace, Notting Hill Autograph letter signed by sender, with annotation by Sir John Herschel. Sends small lens. Its components neither parallel nor concentric; contains water. Suggests new polishing method. Estimates 4-foot lens would cost £7-£8. [John Frederick William Herschel Note: Tested and returned lens. Noted advantages and deficiencies and suggests improvements. Listed others who built similar lenses.] 3 April 1856