The year is established on the assumption that CD was interested in a review of Expression that appeared in St. Paul’s Magazine in February 1873. CD’s regular bookseller was Williams & Norgate.
The February 1873 issue of St. Paul’s Magazine included a review of Expression by William Brighty Rands, writing under the pseudonym Henry Holbeach (Holbeach 1873). There is a lightly annotated copy of the review in the Darwin Pamphlet Collection–CUL, and Expression 2d ed., edited by Francis Darwin, includes a quotation from the review on p. 266, n. 2.