All these sets of pieces were written in good faith for the harpsichord as well as for the organ. But in reality, except in so far as certain principles of form are valuable to all music, and a few figures of musical ornamentation are common to all keyboard music, harpsichord music profits but vicariously from Frescobaldi. His music is essentially organ music, and the development it marks as accomplished, and that toward which it points, are proper to the organ and not to the harpsichord. To the one instrument breadth and power are fitting, to the other lightness and fleetness. Inasmuch as the same distinction exists between the organ and the pianoforte at the present day, with some allowances made for improvements in the mechanism of the organ and for the great sonority of the pianoforte, which allowances affect only the degree but not the kind of differences, Frescobaldi can be said to have influenced the development of pianoforte music only by what he contributed toward the solution of very general problems of form and structure. The same must be said of many other great organists of his and of later days, such as Zweelinck, Samuel Scheidt, Buxtehude, Bohm, Pachelbel, and others. It may be noted that after the death of Frescobaldi the art of organ-playing passed from Italy, the land of its birth and first considerable growth, to Germany. Here a great line of virtuosi added more and more to the splendor and dignity of organ music, perfecting and embellishing style, inventing new forms and making them firm. They remained loyal to the polyphonic style, partly because this is almost essentially proper to the organ with its unlimited power to sustain tone; partly because it is the impressive and noble style of music most in keeping with the spirit of the church, from which the organ will apparently never be wholly dissociated.[3] It cannot be said that this style is in any measure so fitting to the harpsichord and the clavichord or to the pianoforte. For these, a markedly different sort of polyphony has been devised. But so long as organists alone walked in music with the power of assurance--and they were well in command of the problems of their special art while other instrumentalists and writers of operas were floundering about--so long did their influence keep instrumental music in sway.