Beauty from the Symmetry of Their Form:
The Invention of the Kaleidoscope
In 1817, Sir David Brewster patented
the kaleidoscope. Others had noticed the effect of two mirrors
meeting at an angle before, as recounted in this selection from an
1818 article in The Edinburgh Magazine and Literary Miscellany:
The repetition and reversion of images in a glass is
noticed in the Masfiti Naturalis of Baptista Porta, a
Neapolitan nobleman, who flourished about the latter part of the
sixteenth century, and was distinguished for his zeal in promoting
philosophical pursuits…
In the Ars Magna Lucís et Umbra of Kircher,
printed in 1646, we have an account of the same circumstance, and
also of the repetition of the sectors round the centre of the circle:
“A wonderful property,” says he, “and one which
has not, as far as I know, been observed by any one, is exhibited
with two specula, so constructed as to open and shut like a book; and
placed on any plane in which you have described a semicircle divided
into its degrees. For, if the point in which the specula meet be
placed in the centre of the semicircle, so that the side of each
speculum shall stand upon the diameter, the image of an object will
only be seen once, and two objects will appear, one without the
specula, the true one,—and one within, the image. But if the sides
be placed at an angle of 120°, you will see the image of the object
within the specula twice, that is, along with the real image, three
objects But if the specula intercept an angle of 90°, you will see
the circle divided into four parts, and four objects; in the same
manner, at an angle of 60°, you will see a hexagon with six
objects.’1
He then applies the principle to some curious
contrivances which, by his own account, filled his spectators with
astonishment. With one candle he shows how to make a complete
chandelier. “With angles of 120°, 72°, and 45°, you will see,”
says he, “with no less delight than admiration, a chandelier with
three, with five, and with eight branches.”
1 Athanasius
Kircher, Ars Magna Lucís et Umbra, 1646
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