The most curious specimen of minute workmanship, however, with which we are acquainted, is a high-pressure engine, the work of a watchmaker having a stand at the Polytechnic Institution, and first exhibited in 1845. Each part was made according to scale, it worked by atmospheric pressure, in lieu of steam, with the greatest activity, yet it was so small, that it stood on a fourpenny-piece, with ground to spare, and, with the exception of the fly-wheel, it might be covered with a thimble. D’Alembert describes a flute-player, constructed by Vaucanson, which he saw exhibited at Paris in 1738. The writer has also seen one, in which a figure appeared seated, and then rose and played a tune, the motions of the fingers seeming to accord with the notes. He cannot answer for the music having been produced by the movements of the hands of the automaton. D’Alembert affirms, however, that the automaton of Vaucanson really projected the air with its lips against the embouchure of the instrument, producing the different octaves by expanding and contracting their openings, giving more or less air, and regulating the tones by its fingers, in the manner of living performers. The height of the figure, with the pedestal, containing some of the machinery, was nearly six feet; it commanded three octaves, several notes of which musicians find it difficult to produce. Some years ago, two automaton flute-players were exhibited in this country, of the size of life, which performed ten or twelve duets. That they actually played the flute might be proved, by placing the finger on any hole that was unstopped for a moment by the automata. M. Vaucanson produced a flageolet-player, who beat a tambourine with one hand. The flageolet had only three holes, and some notes were made by half-stopping these. The lowest note was produced by a force of wind equal to an ounce, the highest by one of fifty-six French pounds. A duck was, however, considered to be his chef-d’œuvre; it dabbled in the mire, swam, drank, quacked, raised and moved its wings, and dressed its feathers with its bill; it even extended its neck, took barley from the hand and swallowed it, during which process the muscles of the neck were seen in motion, and it also digested the food by means of materials provided for its solution in the stomach. The inventor made no secret of the machinery, which excited, at the time, great admiration.