The last automaton of Hero to which I shall refer is perhaps the most ingenious of all, and it is one that those who were present when Brother Manning gave us his discourse on Robert-Houdin have already seen, I mean the little figure whose head cannot be severed from his body no matter how many times a knife be passed through his neck. Thanks to the kindness of my good friend I can show you one of these beautiful figures presented to me by him, and it will, I think, be of interest to him and to you to know that this device was invented nearly 2,000 years before Robert-Houdin was born, and a description of it with accompanying figures may be seen to-day in the British Museum in a Greek manuscript of the fifteenth century, which is a copy of Hero’s Σπειριταλια, and I now throw on the screen a carefully made facsimile (Fig. 12) of the figure given in that manuscript (which is known as No. 5605 of the Harleian Collection). [Illustration:-HARLEIAN MANUSCRIPT-(FIFTEENTH CENTURY)-Fig. 12.] The head of this figure, which is otherwise separate from it, is attached to it by a peculiar shaped wheel pivotted between the shoulders of the body. This wheel may be described as a circular disc having an expanded rim so that a section taken through a radius would be of the form of the letter =T=, out of this wheel three nearly semicircular gaps are cut, each occupying sixty degrees of the circumference, and therefore leaving three portions of the rim, each also of sixty degrees. The neck attached to the head is fitted with a hollow =T= shaped circular groove into which the =T= ended arms of the wheel pass in succession as the wheel is rotated. As the groove in the head occupies nearly sixty degrees it follows that as the wheel is rotated the rim of one arm can never leave the groove before the rim of the following arm has entered it, and so the head is attached to the body in every position of the wheel. When the knife is passed between the head and the body it strikes against one of the spokes of the wheel, moving it forward and pushing one of the arms out of the groove in the head, while, at the same time, another, following behind the knife, takes its place, and thus the head can never be detached from the body. Such an automaton is the little negro which I hold in my hand, for which I am indebted to the fraternal generosity of Brother Manning. Hero’s description, however, carries the ingenuity of the device considerably farther, for in his automaton, not only is it impossible to sever the head from the body by passing a knife through the neck, but the figure can actually drink both before and after the operation. The illustration on the screen (Fig. 13) is a sort of modern restoration of the Harley drawing, showing the disposition of the various parts of the mechanism. (A) represents the wheel by which the head is held on to the body, and it will be noticed that a tube D D leads from the mouth to the neck and another, E, from the neck through