Under this arrangement, no matter how slowly the key is depressed, the action produces sound, and also enables the hopper to repeat a blow with a partially risen key. The damper (a) is beneath the string (g) and is pushed up by the spring (m). This double escapement action was invented by Sebastian Erard and patented by his nephew, Pierre Erard, in 1821, but did not succeed in obtaining public recog nition until after 1835. While not demanding as high a finger movement as the English action, it is uniform in the variety and directness of blow.
The Herz-Erard repetition action shown in Fig. 9 is a simplified form of the Erard action just described. It was first employed in the grand pianos of Henry Herz of Paris, but, owing to its economy and efficiency, has been adopted with slight modifications by many of the most prominent piano-makers. Next to Erard the most prominent piano manufacture in France was Pape, a native of Hanover. In 1827 he invented a down-striking action, of which the mechanism was above the strings. During the latter part of the 18th century the desire to save space originated the idea of mak ing musical instruments of this class in an up right form. The first attempts were merely to turn the horizontal pianos, spinets and harpsi chords into a vertical position on a stand. In the year 1800 John Isaac Hawkins, an English man, living in Philadelphia, Pa., invented the first genuine upright piano and patented it in the United States and England. He called it the Portable Grand Pianoforte, and it is re markable as containing most of the features characteristic to the modern upright. The idea was further developed and improved by South well in 1807, who produced the now obsolete but beautiful toned "Cabinet," and by Wornum, who produced a low upright with diagonal strings, in 1811, and one with vertical strings in 1813.
Fig. 10 shows the Wornum upright piano action, as made by Broadwood: (k) is the key, (b) the hopper, (d) the hammer-butt, holding the shank of the hammer-head (e); (c) is the check, (f) the damper, (i) the set-off button, (I) the spiral hopper spring invented by Bord, (m) the pilot, employed to raise the hopper and its crank to the height required for their service, and the tape (n), which, being tight ened by the rise of the hammer when the key is struck, pulls the hammer back when the key returns and thus assists the repetition. Because
of the small floor space occupied the upright piano became the instrument for the million, but it can never be the choice of the artist, be cause it smothers the vibrations, which can he brought out fully irr a grand piano.
A modern piano consists of the following parts: (1) The °case," made of rosewood, mahogany, walnut, cherry, maple or other hard wood, and, according to its form, classified as grand, square or upright. The grand pianos are triangular in body and are built in various sizes, from tho full concert grand, 8 feet 10' inches in length, to the baby grand, six feet long, and adapted to parlor use. The square form is no longer built, having been entirely superseded by the upright for use in private houses. The outer side of a piano case is usually veneered over the solid wood. Some makers build their piano cases of material made of several thicknesses of wood, under the sup position that it assists the resonant qualities. Some cases arc very elaborately carved and others expensively inlaid. Special instruments have been made costing as high as $50,000. (2) The "frame," now almost universally made of iron or steel, held within the case and in separable from it. (3) The "string-plate," at tached to the rear end of the frame and to which the strings are fastened. (4) The "wrest plank," attached to the front end of the frame and holding the tuning pins, around which one end of the strings is wound, so that their ten sion is regulated by turning the pins. The wrest-plank has to be made very solid to ensure the rigidity necessary to withstand the enor mous strain of the strings, a tension amounting to from 10 to 20 tons.
(5) The "belly" or "sounding-board," a thin piece of wood placed under the strings to in crease the sound produced by their vibrations. Owing to their small diameter and consequent limited contact with the air, the sound produced by strings vibrating freely is so weak that a resonance factor is necessary. This factor is supplied by the belly upon which hardwood bridges are glued, which transmit the vibrations of the strings to the belly and thus creates sym 'athetic vibrations of the woody substance so as to adequately increase the sound. The manu facture of sounding-boards is an important branch of the industry and elaborate planing and Blueing machinery is utilized.