Undated, but Preface dated 1898. A hand-written letter, dated 1899, from the author to a Mr Picton-Frances is left laid in. Thomas Bolas (1848-1932) was an active member of the Royal Photographic Society and developed a camera which he referred to as a ‘detective camera’ and the design for which formed the basis of several popular cameras, including William Schmid’s Patent Detective Camera. His letter-head describes his work address as ‘Chemical, Technological and Physical Laboratories’. Grey cloth-covered boards, black decoration to front board, black titles to spine, 212 pages. With three leaves of advertisements to the rear, and a four page advertisement for the book (including many review snippets) left laid in. Condition: Boards rubbed, soiled and worn. Some age-darkening to pages, a little foxing to end papers, but binding firm and pages on marked. There is offsetting to pages 12 and 13, from a publisher’s bookmark left laid in.