d.

But this difference is not so important as it appears. The part song
method was at the basis of all these old lute songs. This is well proved
by the fact that before the end of the century the device of turning
part songs into solo pieces with lute accompaniment had become quite
familiar. It was so common that we are driven to something more
substantial than a mere suspicion that Casella and Minuccio employed a
similar method and that the domination of polyphonic thought in music
had spread from the regions occupied by the church compositions of Dufay
and his contemporaries downward into the secular fancies of people whose
daily thought was influenced by the authority of the church.

Furthermore this method of turning part songs into solos survived until
the era of the full fledged madrigal dramas of Vecchi in the latter part
of the sixteenth century, and at what may be called the golden era of
the frottola was generally and successfully applied to that species of
composition. Whatever the troubadours and minnesingers may have done
toward establishing a metrical melodic form of monophonic character was
soon obliterated by the swift popularity of part singing and the immense
vogue of the secular songs of the polyphonic composers. When the desire
for the vocal solo made itself felt in the exquisitely sensuous life of
medieval Italy, it found its only gratification in the easy art of
adaptation. In such scenes as those described by Boccaccio and much
later by Castiglione there was no incentive to artistic reform, no
impulse to creative activity.

We find ourselves, then, equipped with these significant facts: first,
that the composition of secular music in polyphonic forms was at least
as old as the thirteenth century; that part singing was practised in
Italy as far back as the fourteenth century; that songs for one voice
were made with Italian texts at least as early as the time of Dante and
Boccaccio; that the art of arranging polyphonic compositions as vocal
solos by giving the secondary parts to the accompanying instrument was
known in the time of Minuccio and Casella; that at the time of
Poliziano's "Orfeo" the frottola was the reigning form of part song, and
that then and for years afterward it was customary to arrange frottole
as solos by giving the polyphony to the lute or other accompanying
instrument.

It seems, then, that we shall not be far astray if we conclude that the
solo parts of Poliziano's lyric