A quincunx is an arrangement of five objects, four of them at the vertices of a square or rectangle, and the fifth at its centre. About 1873 Fr. Galton invented a simple device which he called quincunx. It showed that shot, falling through an array of pins, collected in a figure resembling a normal curve. The authors describe Galton's work at the time; argue that the quincunx was his natural-scientific approach to the central limit theorem (CLT); dwell on the generalizations of that device (Galton himself; Pearson, in 1895); and provide an appropriate mathematical background. They did not remark that the conditions for the CLT established at the time were less restrictive than Galton thought (p. 149) and their expression (p. 159) ``the percentage of balls \dots converges to infinity'' was unfortunate. That Galton invented identification by fingerprints (p. 144) is wrong: he had predecessors, see ``Fingerprints'' in New Enc. Brit., 15th ed., vol. 4.