Date from preface; otherwise undated. Red cloth-covered boards, decorative titles to front board, pictorial advertisements to front and rear pastedown (one for a WC bowl and another for a flushing system, with diagram), 83 pages with many diagrams. Front free end paper comprises an extract from publisher’s catalogue, while there is a 4-page advertisement to the rear for Dr Vacher’s Box of Model Bricks (Price 2s 6d., with Book of Instruction). Condition: Boards very faded, patchily, and soiled. Pages clean and unmarked, with some age-darkening.