Royal Anthropological Institute of Great Britain and Ireland · London, Anthropological Institute · leaf 69
: — 1. At what distance cau he distinguish the form of a human figure moving ? 2. At what distance can he distinguish a man on horseback 1 The existence of Myopia, where suspected, may be ascertained by the improvement gained by the use of biconcave (short-sighted) spectacles. J. ±5. Further Notes… … distinguished from another of the same size that has one of its diagonals vertical as in Fig. 2. These two figures represent the opposite faces of the same card (or of painted zinc, which would be more durable), which is intended to be hung against a rather dark background. Procure three such…
Internet Archive · Smithsonian Libraries · Public domain (published before 1931). Free to use for anything.
