1. On the focal length of microscopic objectives Author(s): Cross, Charles R. (Charles Robert), 1848-1921 Publication: [Boston?] : [publisher not identified], [1870?] Subject(s): Microscopy -- instrumentationLenses
2. Table showing the actual magnifying power of thirty-five microscopical objectives of various makers, as determined at a meeting of the Bailey Microscopical Club, held in New York, September 20, 1870 Author(s): Curtis, Edward, 1838-1912, author Publication: [New York?] : [publisher not identified], [1870] Subject(s): Microscopy -- instrumentationLenses
