Mount the transparency on a light circular frame, on an axis easily
turned. Close the upper end of the hollow cylinder with a disc of tin,
cut into inclined planes like the ventilator let into window panes
(fanlight).
A lamp placed inside the cylinder will illuminate the transparency at
the same time that it makes it turn round by the current of heated air
striking the tin plate.
Vary the subject of the pictures as you please. Mr. Panky’s represent
hideous serpents twisting round a column, and other delicious
spectacles.
* * * * *
[Illustration: Fig. 56.]
To make the above magical figure without taking the hand off, begin at
A, thence to B, to C, to D, to E, and so on.