This clumsy contrivance indicated _relative_ pitch well enough, but _not_ the _key_—or the duration. The next step was to use lines—which varied in number—upon or between which the Neumes, which gradually changed to square notes, were written. The pitch was indicated by using a _red_ line for F, and a _yellow_ or _green_ line for C. A further improvement was, to put the letters F or C and later G on one of the lines at the beginning; the modern clefs are simply modifications of these letters. =Characters to Indicate Duration=.—The honor of suggesting characters to indicate _duration_ is usually attributed to =Franco of Cologne=, an ecclesiastic who lived in the latter part of the 12th century; but as in the case of Gregory and Guido, we must believe that his name simply stands as representative of a period. A system is rarely the work of one man, rather a development from the labor of many. Franco’s treatise on the subject marked an epoch. Up to the end of the 13th century the notes in use were the Longa, Brevis, and Semibrevis, as well as the Duplex Longa, or Maxima. The smaller values, the Minima, and the Semiminima first occur about 1300. About the middle of the 15th century white notes were introduced in place of certain of the black, the latter color being reserved only for the smaller note values. The signs underwent some change at this time. Maxima, Longa, Brevis, Semibrevis (our whole note), Minima (half note), Semiminima (quarter), Fusa (eighth), Semifusa (sixteenth). [Illustration: Longa Brevis Semibrevis Duplex Longa or Maxima Minima Semiminima] [Illustration: Maxima Longa Brevis Semibrevis Minima Semiminima Fusa Semifusa] =The Beginnings of Harmony=.—Our information as to the beginning of Harmony is very vague and uncertain. As early as the Saxon times in England some rude kind of part singing, without written rules apparently, seems to have existed. The first intimations we have of any scientific attempts are _Faburden_ or _Falsoborden_ and Diaphony or Organum. Faburden consisted of singing a melody while another voice sang a _drone_ accompaniment below it; thus: [Music] Diaphony or Organum consisted of a succession of _fourths_ or _fifths_ and _octaves_, thus: [Music: Two Parts Three Parts] It has been denied by some authorities that such a barbarous manner of singing ever existed; but two considerations have been lost sight of, in making this denial: First, the fourth, fifth and octave were esteemed the _only consonances_. Secondly, the undisputed fact that as late as the time of Chaucer, if not later, what was called “discanting quatible” or “quinable” existed; this discanting was done as follows: The performer while singing a melody accompanied himself on the lute, playing the _same melody a fourth or fifth above_. It can hardly be doubted that a style of performance that was esteemed in the 15th, was perfectly satisfactory to the ears of the 10th century.