London: T. & R. Willats, 1851. Fourth edition with additions. 16mo., 48 pp., errata, illustrations. Half morocco and cloth with original front wrapper bound in. Slight staining and soiling, with creasing to a few leaves and the blank margin of 4 leaves trimmed 1/8 inch shorter than the remainder of the text; several corners are chipped or rounded from wear with no loss of text. A good copy. Item #26314
This manual describes the calotype and other processes on paper, including ammonia as an additive, coloring paper photographs, and a new method of preparing positive paper photographs. The last four pages are a priced list of photographic apparatus, chemicals and materials available by order from Thomas and Richard Willats, London. The author's note on the verso of the title page indicates that the third edition consisted of 1000 copies.
WorldCat locates only two copies, both at the British Library. Roosens and Salu No. 6363; Gernsheim No. 671.