Page:Encyclopædia Britannica, Ninth Edition, v. 19.djvu/84

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74 installation of his invention. On his death-bed he com mended it to Broadwood s care, but Stodart appears to have been the first to advance it, Broadwood being pro- Fio. 24. Broadwood s Grand Piano Action, 1884. English direct mechanism. bably held back by his partnership with his brother-in-law, the son of Shudi, in the harpsichord business. (The elder Shudi had died in 1773.) Stodart soon made a con siderable reputation with his " grand " pianofortes, a FIG. 25. Collard s Grand Piano Action, 1884. English action, with reversed hopper and contrivance for repetition added. designation he was the first to give them. In Stodart s grand piano we first find an adaptation from the lyrichord of Plenius, of steel arches between the wrest-plank and bellyrail, bridging the gap up which the hammers rise, in itself an important cause of weakness. These are not found in any contemporary German instruments, but may have been part of Backers s. Imitation of the harpsichord by "octaving" was at this time an object with piano makers. Zumpe s small square piano had met with great success ; he was soon enabled to retire, and his imitators, who were legion, continued his model with its hand stops for the dampers and sourdine, with little change but that which straightened the keys from the divergences inherited from the clavichord. John Broadwood took this domestic instru ment first in hand to improve it, and in the year 1780 succeeded in entirely reconstructing it. He transferred the wrest-plank and pins from the right-hand side, as in the clavichord, to the back of the case, an improvement uni versally adopted after his patent, taken out in 1783, expired. In this patent we first find the damper and piano pedals, since universally accepted, but at first in the grand pianofortes only. Zumpe s action remaining with an altered damper, another inventor, John Geib, about this time patented the hopper with two separate escape ments, one of which soon became adopted in the grass hopper of the square piano, it is believed by Geib him self ; and Petzold, a Paris maker, appears to have taken later to the escapement effected upon the key. We may mention here that the square piano was developed and continued in England until about the year 1860, when it went out of fashion. To return to John Broadwood, having launched his reconstructed square piano, he next turned his attention to the grand piano to continue the improvement of it from, the point where Packers had left it. The grand piano was in framing and resonance entirely on the harpsichord prin ciple, the sound-board bridge being still continued in one undivided length. The strings, which were of brass wire in the bass, descended in notes of three unisons to the lowest note of the scale. Tension was left to chance, and a reasonable striking line or place for the hammers was not thought of. Theory requires that the notes of octaves should be multiples in the ratio of 1 to 2, by which, taking the treble clef C at one foot, the lowest F of the five-octave scale would require a vibrating length between the bridges of 12 feet. As only half this length could be conveniently afforded, we see at once a reason for the above-mentioned deficiencies. Only the three octaves of the treble, which had lengths practically ideal, could be tolerably adjusted. Then the striking-line, which should be at an eighth or not less than a ninth or tenth of the vibrating length, and had never been cared for in the harpsichord, was in the lowest two octaves out of all proportion, with corresponding dis advantage to the tone. John Broadwood did not venture alone upon the path towards rectifying these faults. He called in the aid of professed men of science Cavallo, who in 1788 published his calculations of the tension, and Dr Gray, of the British Museum. The problem was solved by dividing the sound-board bridge, the lower half of which was advanced to carry the bass strings, which were still of brass. The first attempts to equalize the tension and improve the striking-place were here set forth, to the great advantage of the instrument, which in its wooden construc tion might now be considered complete. The greatest pianists of that epoch, except Mozart and Beethoven, were assembled in London, Clementi, who first gave the pianoforte its own character, raising it from being a mere variety of the harpsichord, his pupils Cramer and for a time Hummel, later on John Field, and also the brilliant virtuosi Dussek and Steibelt. To please Dussek, Broad- wood in 1791 carried his five-octave, F to F, keyboard, by adding keys upwards, to five and a half octaves, F to C. In 1794 the additional bass half octave to C, which Shudi had first introduced in his double harpsichords, was given to the piano. Steibelt, while in England, instituted the familiar signs for the employment of the pedals, which owes its charm to excitement of the imagination instigated by power over an acoustical phenomenon, the sympathetic vibration of the strings. In 1799 Clementi founded a pianoforte manufactory, to be subsequently developed and carried on by Messrs Collard. The first square piano made in France is said to have been constructed in 1776 by Sebastian Erard, a young Alsatian. In 1786 he came to England, and founded the London manufactory of harps and pianofortes bearing his name. That eminent mechanician and inventor is said to Fio. 26. Enird s Double Escapement Action, 1884. The double escapement or repetition is effected by a spring in the balance pressing the hinged level- upwards, to allow the hopper which delivers the blow to return to its position under the nose of the hammer, before the key has risen again. have at first adopted for his pianos the English models.

However, in 1794 and 1801, as is shown by his patents,