Hand-shadows. 'The illustrations will assist those who wish to amuse children by making rabbits, etc, on the wall. The shadows will be seen perfectly thrown if the hands be carefully fixed near a good light.'

Shadow play, the forerunner of all optical developments, has long and universally been a fascination to the extent that in medieval times the Western church stepped in to control a phenomenon which, in the hands of scientists — or rather magicians — could become dangerous. By the early 19^th century, however, things were more relaxed and books of the time give detailed instructions for making screens, cut outs and suitable sources of light.

The musical glasses are tuned by pouring in water, and played with short rods of an undisclosed material. 'If the performer is gifted with a musical ear, he can obtain, by a little arrangement, a perfect Gamut by means of seven glasses which each give a note. A piece of music may be fairly rendered in this manner for the musical glasses frequently produce a very pure silvery sound.' The performance was clear;y an occasion of the utmost gravity. How long the interest of the audience could be held is another matter.