London: Office of the Commissioners of Patents for Inventions, 1868. 12mo, pp (xvi), (226), (10, appendix). Original blue printed paper covers. Covers have some creases, small chips, neat repairs; nicks and very small chips to fore edges of early leaves; corner creases to late leaves; in all, a good, clean & tight copy of a fragile item, no owner names. No illustrations in text. Note: lighter parcel, any default shipping will be reduced.