One of two signed versions of a long letter from Franklin to Lord Kames is dated April 11, 1767, and previous editors have accepted that date without question. For reasons explained in an accompanying head-note the present editors believe the other version, dated Feb. 25, 1767, is closer to Franklin’s original and that the earlier date is the correct one. The letter is therefore printed above, pp. 62–71, rather than here at the April 11 date. Notes to that text indicate the verbal differences between the two versions.