ferocious spirits and four giants, all endeavouring to break through the magic circle the priest had formed. All there were evidently in a most abject state of terror, and remained in the place until the church bells began to ring for morning prayers, when they returned home, the boy declaring that two of the demons preceded them, dancing and gambolling before them, and sometimes running along the housetops. The priest then advised him to try another spiritual _séance_, and endeavour to induce the demons to point out sundry pots of buried gold, so that they all might become rich, but it does not appear that the priest’s advice was followed. It is impossible to read the foregoing description of what happened, without being convinced that the whole affair was an optical illusion, and not the mere result of the imagination of those who took part in it. The smoke was evidently caused in order to afford a field for the exhibition of painted images reflected by concave mirrors, and the circle was formed in order that those within it might be within range of the images formed on the smoke. The mirrors reflecting the images of the demons had undoubtedly already been arranged so that they would fall just above the fire, and become visible when the gums began to burn with a smoky flame. The perfumes were simply to help to stupify the spectators, and aid in working on their imaginations for those occurrences which were beyond the reach of optics, for the poor unfortunate boy saw things that his companions did not, even to a couple of demons dancing through the streets in broad daylight. In fact, it is somewhat difficult to draw the line between reality and imagination in this case. No doubt the story is considerably exaggerated by Cellini, who was a fervid Italian, and prone to believe in wonders, as is instanced by his wish to study the black art. The priest, too, whom he describes as a man of genius, no doubt had a great influence over the famous artist, and made him see a great deal more than was really there. The introduction of the magic lantern provided the magicians of the seventeenth century with a very powerful instrument with which to continue their deceptions. The use of the concave mirror, which does not appear to have had any accessories worth speaking of, required a separate apartment, or at least a hiding-place of some sort that was difficult to discover under ordinary circumstances; but the magic lantern, inclosing as it did the lamp, the optical apparatus, and the figures in a comparatively small spice, was particularly appropriate to the wants of the Homes and Davenports of the day, who until then had never possessed anything so convenient and portable. [Illustration: FIG. 50.—Section of the Magic Lantern. ]