How, then, did the great organists of the sixteenth and the seventeenth century affect the growth of pianoforte music? By establishing certain forms, notably the fugue, which have been adapted to every kind of serious instrumental music and to the pianoforte with only less propriety than to the organ; by helping to lay the harmonic foundation of music which, as we have said, is the basis for all music down to the present day and is but now being forsaken; by discovering the effectiveness of certain styles of ornamentation and runs which are essentially common to all keyboard instruments. They helped to give music a form made of its own stuff, and a beauty and permanence which is the result of such form perfected. In their workshops two of such forms were rough-hewn which proved of later service to pianoforte music--the harmonic prelude and the fugue. We must look elsewhere for the development of other forms, less perfect perhaps, but no less important in the history of pianoforte music. Such are the rondo and the variation form. The rondo may be mentioned here because of its great antiquity. Like the ballade, it was originally a dance song, really a song with a burden and varying couplets. No form could be simpler. The burden recurring regularly gives an impression of unity, which, only in case of too many recurrences, has the fault of monotony. The varying couplets, constituting the episodes between the reiterations of the burden or main theme, offer variety and contrast. Yet, in spite of the merits of this scheme of musical structure, the form was little used by composers down to the beginning of the eighteenth century. Relatively long pieces of music, in which the rondo form could be used, were generally written in the style of fugues. Furthermore, until the harmonic art was developed and the contrast of keys appreciated, the episodes, being restricted by the old modal laws to the tonality of the main theme, would be in a great measure without the virtue of contrast. The variation form, on the other hand, was greatly used, conspicuously so by a number of writers for the virginal in England, whose works, surviving in several ancient collections, form a unique and practically isolated monument in the history of pianoforte music. These collections have often been described in detail and carefully analyzed. The most comprehensive is that long known as the Queen Elizabeth Virginal Book, now called merely the Fitzwilliam Collection, a beautifully worked manuscript preserved in the Fitzwilliam Museum at Cambridge. Others are Benjamin Cosyn’s Virginal Book and Will Foster’s, both of which are at Buckingham Palace; a smaller book, known as Lady Nevile’s Book, and the _Parthenia_, famous as the first collection of virginal music printed in England.