With this scheme of Keys Ptolemy combined a new method of naming the individual notes. The old method, by which a note was named from its relative place in the Perfect System, must evidently have become inconvenient. The Lydian Mesê, for example, was two tones higher than the Dorian Mesê, because the Lydian scale as a whole was two tones higher than the Dorian. But when the two scales were reduced to the same compass, the old Lydian Mesê was no longer in the middle of the scale, and the name ceased to have a meaning. It is as though the term 'dominant' when applied to a Minor key were made to mean the dominant of the relative Major key. On Ptolemy's method the notes of each scale were named from their places in it. The old names were used, Proslambanomenos for the lowest, Hypatê Hypatôn for the next, and so on, but without regard to the intervals between the notes. Thus there were two methods of naming, that which had been in use hitherto, termed 'nomenclature according to _value_' ([Greek: onomasia kata dynamin]), and the new method of naming from the various scales, termed 'nomenclature according to _position_' ([Greek: onomasia kata thesin]). The former was in effect a retention of the Perfect System and the Keys: the latter put in their place a scheme of seven different standard Systems. [Footnote 1: _Harm._ ii. 11 [Greek: hôste mêd' an heteron eti doxai tô eidei ton tonon para ton proteron, all' hypodôrion palin, ê ton auton hypophrygion, oxyphônoteron tinos ê baryphônoteron monon.]] In illustration of his theory Ptolemy gives tables showing in numbers the intervals of the octaves used in the different keys and genera. He shows two octaves in each key, viz. that from Hypatê Mesôn ([Greek: kata thesin]) to Nêtê Diezeugmenôn (called the octave [Greek: apo nêtês]), and that from Proslambanomenos to Mesê (the octave [Greek: apo mesês]). As he also gives the divisions of five different 'colours' or varieties of genus, the whole number of octaves is no less than seventy. Ptolemy does not exclude difference of pitch altogether. The whole instrument, he says, may be tuned higher or lower at pleasure[1]. Thus the pitch is treated by him as modern notation treats the _tempo_, viz. as something which is not absolutely given, but has to be supplied by the individual performer.