London: Kegan Paul, 1911. hardcover. Delivered before the Royal College of Surgeons of England on February 1st and 3rd, 1911. Illustrated. Slim 8vo, 76 pages, original maroon cloth. London, 1911. First Edition. Very good (+).
BOA 2656. This work contains an account of the author's well known "Lantern Test" (pp. 53 ff.) for colour-blindness in place of the Holmgren test.