Besides, certain deviations from the diatonic major scale, which we meet with in the music of foreign nations, possess a particular charm, which we are sure to appreciate more and more as we gradually become familiar with them. This, for instance, is the case with the Superfluous Second introduced as an essential interval of the scale. Many of our musicians regard such intervals as whimsical deviations, which ought not to be liked because they do not well agree with the rules laid down in our treatises on the theory of music. To such learned Professors the scale of the Arabs, with its seventeen intervals in the compass of an octave, instead of twelve semitones, as in our own system, is of course a flagrant misconception--not to speak of the twenty-two demi-semitones of the Hindus, which ought to be twenty-four. Those nations have musical systems very different from ours, for which their order of intervals is well suited. Our rules of harmony and forms of composition are unknown to them; still, their popular legends and traditions clearly prove that they appreciate the beauty and power of music not less keenly than we do; and they demonstrate the superiority of their scales with the same confidence as any of our theorists are capable of displaying. Could we trace our diatonic Major Scale in the songs of birds and in the euphonious cries of certain quadrupeds, we should have a more cogent reason for regarding it as the most natural scale than is afforded by a comparison of the vibrations required for the production of its several intervals. The songs of various birds have been written down in notation, from which it would appear that these feathered songsters possess an innate feeling for the diatonic major scale; but, unfortunately, unless the melodious phrases, or passages, thus noted down are distinguished by some remarkable rhythmical peculiarity, they are seldom easily recognizable when they are played on a musical instrument. There may be among the numerous birds a few which in their natural song, untaught and uninfluenced in any way by man, emit a small series of tones strictly diatonic; but no such musicians are to be found among our own birds, although we have in Europe the finest singing birds in existence. The nightingale, it is true, produces occasionally a succession of tones which nearly corresponds with the diatonic Major Scale in descending, and which might possibly be mistaken for it by a listener charmed by the exquisite purity and sweetness of the tones which he does not investigate with the ear of a pianoforte-tuner. Even the two melodious sounds of the cuckoo cannot be properly written down in notation; nor can they be rendered on the pianoforte, because they do not exactly constitute a Major Third, for which they are generally taken, and still less a Minor Third. A certain ape of the Gibbon family is said to produce exactly the chromatic scale through an entire octave in ascending and descending.