swell and main keyboards of an organ.  At last it occurred to lovers of music that all refinement of musical expression depended on touch, and that whereas a string could be plucked or pulled by machinery in but one way, it could be hit in a hundred ways.  It was then that the notion of striking the strings with a hammer found practical use, and by the addition of this element the piano-forte emerged into existence.  The idea appears to have occurred to three men early in the eighteenth century, almost simultaneously—­Cristofori, an Italian, Marins, a Frenchman, and Schroter, a German.  For years attempts to carry out the new mechanism were so clumsy that good harpsichords on the wrong principle were preferred to poor piano-fortes on the right principle.  But the keynote of progress had been struck, and the day of the quill and leather jack was swiftly drawing to a close.  A small hammer was made to strike the string, producing a marvelously clear, precise, delicate tone, and the “scratch” with a sound at the end of it was about to be consigned to oblivion for ever and a day.

Gottfried Silbermann, an ingenious musical instrument maker, of Freyhurg, Saxony, was the first to give the new principle adequate expression, about the year 1740, and his pianos excited a great deal of curiosity among musicians and scientific men.  He followed the mechanism of Cristofori, the Italian, rather than of his own countrymen.  Schroter and his instruments appear to have been ingenious, though Sebastian Bach, who loved his “well-tempered clavichord” (the most powerful instrument of the harpsichord class) too well to be seduced from his allegiance, pronounced them too feeble in tone, a criticism which he retracted in after years.  Silbermann experimented and labored with incessant energy for many years, and he had the satisfaction before dying of seeing the piano firmly established in the affection and admiration of the musical world.  One of the most authentic of musical anecdotes is that of the visit of John Sebastian Bach and his son to Frederick the Great, at Potsdam, in 1747.  The Prussian king was an enthusiast in music, and himself an excellent performer on the flute, of which, as well as of other instruments, he had a large collection.  He had for a long time been anxious for a visit from Bach, but that great man was too much enamored of his own quiet musical solitude to run hither and thither at the beck of kings.  At last, after much solicitation, he consented, and arrived at Potsdam late in the evening, all dusty and travel-stained.  The king was just taking up his flute to play a concerto, when a lackey informed him of the coming of Bach.  Frederick was more agitated than he ever had been in the tumult of battle.  Crying aloud, “Gentlemen, old Bach is here!” he rushed out to meet the king in a loftier domain than his own, and ushered him into the lordly company of powdered wigs and doublets, of fair dames shining with jewels, satins, and velvets, of courtiers glittering in all the colors of the rainbow.  “Old Bach” presented a shabby figure amid all this splendor, but the king cared nothing for that.  He was most anxious to hear the grand old musician play on the new Silbermann piano, which was the latest hobby of the Prussian monarch.