Visual illusions, their causes, characteristics and applications (1922)
Luckiesh, Matthew, b. 1883 · New York, D. Van Nostrand Company · leaf 74
61 TYPES OF GEOMETRICAL ILLUSIONS physical dimensions, actually appears much larger. Here is a case where experience, allowing for a di- minution of size with increasing distance, actually causes the column on the right to appear larger than it really is. The artist will find this illusion even more … Fig. 25. — Distortion of a square due to superposed lines. striking if he draws three human figures of the same size but similarly disposed in respect to perspective lines. Apparently converging lines influence these equal figures in proportion as they suggest perspective. Although they are not…
Optical illusions
Internet Archive · University of California Libraries · Public domain (published before 1931). Free to use for anything.
![An illustration from Eyn schön nützlich Büchlin vnd Vnderweisung der Kunst des Messens mit dem Zirckel, Richtscheidt oder Linial : zu nutz allen Kunstliebhabern fürnemlich den Malern, Bildhawern, Goldschmiden, Seidenstikern, Steynmetzen, Scheinern auch allen Andern so sich der Kunst des Messens (Perspectiua zü latin gnant) zügebrauchen Lust haben : darin Man auch solche Kunst leichter dan ausz etzlichen hieuorgetruckten Büchern begreiffen vn lernen mag mit vil [i.e., 56] schönen darzü dienenden Figuren (1531)](https://img.insideoutlibrary.com/img/200/ia-eynschnntzlichbc00rodl-27-43.webp)
![An illustration from Il terzo [-qvinto] libro ... (1551)](https://img.insideoutlibrary.com/img/200/ia-ilterzoqvintolib00serl-73-89.webp)
