The general principle upon which this automaton’s power of selection was founded lay in the fact that in the edge of each medallion there was a small hole drilled, but no two holes were drilled to the same depth, and, by an exceedingly delicate mechanism, the varying depth to which a pin could be thrust into the edge of a disc, was caused to control the mechanism by which the various answers were selected, and which were exhibited when the little door flew open. The next great master of automaton design and construction, was that wonderful genius Robert-Houdin (about whom our worthy Secretary and Seer discoursed to us so pleasantly and so instructively nearly a year ago). Brother Manning’s paper was so complete in itself, and that part of it which dealt with automata was so ably illustrated, that it will be quite unnecessary for me to add to the length of this communication, by going over that ground again, so I will merely enumerate the automata of that interesting man and pass on to still more recent times. The first of the automata of Robert-Houdin was a confectioner’s shop, in which a pastry-cook came out of the door when requested and offered to the spectators patisserie, bonbons, and refreshments of every description, and within the shop might be seen the assistants making pastry, rolling out the dough, and putting it into the oven. Then he made two clowns, known as Auriol and Débureau. The first of these performed a number of acrobatic feats upon a chair which was held at arm’s length by the other. After this, the figure of Auriol smoked a pipe, and accompanied on the flageolet an air played by the orchestra. Another was an acrobat which performed tricks on the trapèze, and the last to which I shall refer, was his celebrated writing figure, which is illustrated in Brother Manning’s “Opusculum,” No. XXIV., to which I must refer you for a great deal of interesting information respecting that remarkable man. A contemporary of Robert-Houdin was Mons. Mareppe, who constructed a very wonderful automaton violin player, and which was exhibited at the Conservatoire at Paris, in the year 1838, and which performed on the violin by bowing and fingering the strings, and in an account of the performance which was published at the time in “Galignani’s Messenger,” it is stated that the musical execution was so perfect as to bring tears into the eyes of the audience.