In identifying the modal character of the “gapped” tunes I have deemed it advisable to proceed by an entirely arbitrary method, free from any sort of theoretical connotation. Should a missing tone be presupposed to make either a major or minor, perfect or imperfect, interval with the tonic, there arise at once ambiguities of modality. For purposes of harmonic treatment it is quite necessary to decide upon which particular mode a gapped tune suggests, but in studying the purely melodic aspects it is reasonable to accept the tune as an entity, considering it in its actual tonal structure and not with regard to its possible modal permutations. To accomplish this purpose I have evolved a chart, based on methods used by Cecil J. Sharp in his English Folksongs from the Southern Appalachians, which for the great majority of the tunes in this collection is an adequate system of classification. The arrangement of the chart is very simple: there are five columns, each beginning with one of the five pentatonic scales. Immediately below each pentatonic scale are four hexatonic scales which are formed by the addition of the missing tones, singly and in their variable positions. The system permits these variables to be read in terms of natural and flatted tones. Lastly in each column are three regular heptatonic modes which are the outgrowth of supplying both missing tones simultaneously and in variable combination. The gaps in the pentatonic and hexatonic scales are indicated by slurs and the numerical positions from the tonic of the missing tones. The supplied missing tones are indicated by black notes, and in fitting any given tune to any scale on the chart I have endeavored where possible to let these black notes indicate the weak tones. Since it was possible, so far as the actual tonal structure of the tunes was concerned, to have a choice in the placing of them, the device of indicating weak tones was a happy solution to a more careful classification. Above each tune in this book I have indicated the modal and, following this and in parentheses, the tonal pattern of the tune with the heptatonic scale as a norm, that is, treating gapped tunes arbitrarily as broken-down heptatonic tunes. A Roman numeral indicates a major or perfect interval with the tonic; an Arabic numeral a minor interval. In event of augmented or diminished fourths or fifths I have used conventional signs. A gap is indicated by a dash.
As a practical example of classification let us take at random, say, ‘[Weeping Savior]’, a song of the present collection. Counting the tones of the melody we find six with the sixth degree missing. We observe that the tune has a major second, minor third, perfect fourth and fifth, no sixth, and a minor seventh. By transposition we see that from a standpoint of the tonal pattern alone the tune can be listed either as Hexatonic, Mode 2, A or Mode 4, b. But the examination of structural detail shows clearly that 3 being a strong tone and 2 being decidedly weak gives preference to the first classification under Mode 2.
While pentachordal and hexachordal tunes (which do not conform to this system of classification) may be perfect entities, I have, nevertheless, for purposes of uniformity classified them on a heptatonic basis, that is, as heptatonic tunes with the sixth and seventh, or seventh alone, missing respectively. Similarly, while it is somewhat tautological to say, for instance, a tune is heptatonic ionian, I have prefixed the term heptatonic to facilitate identification and to balance the constantly recurrent pentatonic and hexatonic.
An examination of these spiritual folk-tunes reveals a great predominance of gapped scales. Only 23 per cent of them use the full seven-tone series; 44 per cent are hexatonic; 23 per cent are pentatonic; and seven tunes use only from 1 to 5 of their scale.
CLASSIFICATION CHART OF TUNES
The incidence of the different modes has been impossible to ascertain. We are sure of a mode, as Mr. Rufty has noted, only when the scale tones are all represented in the melody. Proceeding however in questionable instances according to the more or less clear modal implication, I have found that about 52 per cent of these tunes may be interpreted as ionian (major), about 30 per cent as aeolian, 7.5 per cent each as dorian[12] and mixolydian, and three tunes as phrygian.
I leave the interpretation of the significance of these figures to others. I venture to suggest however that they will be found to indicate a survival of gapped and modal tunes that is unique in the folk-music of today among peoples of European stock.[13]
A modally constructed tune is, as I have indicated, almost sure to be a folk-tune. And if a melody shows the characteristic gaps, its folk nature is quite assured. Indeed, the complete filling-in of the gaps, creating two half steps, is a sign, though not always a sure one, of art influence.[14]
The above paragraphs show in a general way a few of the more important and evident features by which American folk-tunes may be recognised.[15] Their presence or absence in specific cases has helped me to decide as to the fitness of a tune for acceptance into this collection.
Tunes of Religious and Worldly Folk-Songs Compared
I have indicated above ([page 6]) that many of the present tunes were borrowed outright from secular folk-songs. The tune-to-tune relationships were discovered to some degree, as I have indicated, by accident. A spiritual tune would remind me of a secular one. I would look it up in Sharp or elsewhere, verify the relationship, and note it under the proper song in this collection. Such accidents, however, account for but comparatively few of my related-tune discoveries. In most instances they came to light as the result of a methodical comparison made possible by my having catalogued my spiritual folk-tunes and a large number of secular folk-melodies. I shall not go into a detailed explanation of this cataloguing method here, chiefly because it is one which, though it answered my own purposes well, would probably be found inadequate as a tool for students of comparative melody in general. I shall say merely that the catalog was a card index of tune beginnings, all transposed to a key which had two flats as its signature. The arrangement was based on the scale position or relative pitch of the first few tones. At the beginning of the catalog were those tunes which began on b-flat, then came those beginning on c and so on. The arrangement among those tunes beginning on any one tone, followed the same pitch sequence, from lowest to highest, taking into consideration the second, third, and more notes of the tune beginnings where necessary. That is, my lexicographical arrangement was like that of the dictionary, but with notes on a regular staff taking the place of letters, and with the scale steps taking the place of alphabetical sequence.