Fig. 18.
In the next illustration ([Fig. 18]) we have a beautiful plate from Ramelli, in which another of Hero’s inventions, the group of singing birds is introduced as an ornament in an elaborately furnished room of the period. In this case the water is in the first instance lifted by air being blown in through a pipe by a person concealed behind the wall which in the drawing is broken away to show a mediæval old buffer engaged in this manly performance.
About the middle of the seventeenth century magnetism began to be employed for producing the effects of magic, and that extraordinary versatile all-round Odd Volume, Athanasius Kircher, in his “Magnes sive de Arte Magnetica,” which was published in 1641 (a copy of which I have here), describes and illustrates several automata which depend for their action upon magnetism. Here, for example ([Fig. 19]), he gives a representation of the Dove of Archytas, which by the action of a revolving loadstone, is made to fly around a dial and mark the hours by pointing to the figures on its edge.
Fig. 20.
Time will not permit me to say as much about this curious old book as its quaintness and terribly bad science deserve, I will only show you one more illustration from it in which a wheel is driven round by two Æolipiles in the form of human heads, which blow out jets of steam against the cellular periphery of the wheel, and in the lower figure the little boilers (C and D) which the heads inclose, are shown separately, the nozzle of one pointing upwards, while that of the other has a downward direction.
