Originally a publisher’s file copy, and stamped “LONGMANS, GREEN & CO. LTD. PUBLISHING DEPT. FILE COPY. NOT TO BE TAKEN AWAY”. Blue limp card covers, 50 pages, photographic portrait as frontispiece. One illustration, a line diagram of “The Improved Carbon Filament (Squirted Cellulose) Lamp invented by Sir Joseph Wilson Swan, F.R.S. In 1884”. Condition: Boards a little worn and age-darkened, publisher’s stamp inside covers, one of these stamps crossed out in pencil, otherwise unmarked.