Combination of simple mirrors – childish game or useful tool?
Résumé
The Scottish inventor of the kaleidoscope, Sir David Brewster (1781-1868), examined references to previous combinations of mirrors in his defense of his own invention, The Kaleidoscope, Its History, Theory and Construction (1858). Sir David Brewster who was eager to prove that his invention, dating back to 1816, was genuinely innovative, dismissed the use of what he called “combinations of plane mirrors” as productive of “poor effect”. His examination of the mirror devices described in the works of Gianbattista della Porta (1535-1615) Athanasius Kircher (1601-1680) and Richard Bradley (1688-1732), led him to the conclusion that they could hardly have been the result of any deep technical knowledge of the laws of optics. After looking at Sir David Brewster’s arguments, and the original texts and images he studied, I shall try and give examples of the use of these mirrors up to the twentieth century, since, prior to the digital age, they may have been useful instruments in the construction of elaborate symmetrical images. However, the rare references to these simple devices over the centuries tend to suggest that they were either seldom used or that their uses were hardly ever reported because they were employed only in minor decorative arts and perhaps mostly by women and youngsters.