Letter, from Henry Kater to Sir John Herschel, dated at York Gate Autograph letter signed by sender. Does he want a scale ordered form George Dollond for Wilhelm Struve? Will not be in London when Struve arrives. Has written a paper on the Standards for the Royal Society [of London] and will send John Frederick William Herschel a copy when printed. Comments on the comparison of Standards. 8 June 1830