The recording of spoken verse is another matter. It is not difficult to test a diaphragm carefully through a small range, but to be certain of its action at all the pitches and qualities of the speaking voice is impossible. A stable diaphragm, glass or mica, would have to be used, and careful corrections made for the different vowels.
At best, when the records are satisfactory, nothing can be said for the measurements of intensity but that they represent relations of more or less; the diaphragm has a minimum intensity, below which it does not vibrate, and a maximum intensity, above which the amplitude of its vibrations does not materially increase without breaking into partials and 'blasting.'
The disc recorder, which had for a mount a modified microscope stand, was placed on the shoe of the disc stand and clamped. The wax and disc records were adjusted at known starting-points and the stylus carefully lowered, by the rack and pinion adjustment, to the surface of the disc. After a preliminary trial of the diaphragm the apparatus was started, and when at full speed at least two satisfactory records of the material were taken. When the disc had made a single revolution—a record of some ten or fifteen stanzas—the recorder was fed inward to a new circle on the disc. After the records were taken, a microscope with either 2 or 4 Leitz objective and a micrometer ocular was substituted for the recorder. The phonograph recorder was raised and drawn back to its starting point, and the disc came back to its original position. The microscope was focussed, and adjusted by the screw of the shoe until it had the record line in its field; the micrometer furnished an object of reference in the field. The phonograph, now carrying the reproducer—if possible without a horn, as the tones are truer—was started. At the first syllable of the record the apparatus was stopped by the device furnished on the 'Commercial' phonograph, and the plate was turned by adjusting the screw at the phonograph carriage, which changed the length of the chain connecting the two records, until the record of the first syllable was at some chosen point in the field. In cases of records of poetry it was found better to have a set of syllables, say 'one, two, three' prefixed to the record, for this adjustment. The phonograph was again started, and the curve-forms representing the spoken syllables filed past the point as the phonograph repeated each syllable. The rate was slow enough, with the objective 2, so that there was no difficulty in observing the passing syllables. After the conformity of the phonograph record had been noted by the operator, and the subject had passed judgment on the phonograph as saying satisfactorily what he had said, the curve-forms were measured with the micrometer. The record was fed slowly through the field by means of the chain screw on the phonograph carriage; and measurements of the lengths of syllables gave their time values. The micrometer was passed back and forth across the form by the shoe screw, for the measurements of amplitude (intensity). The micrometer measurements in this case could be made at least as rapidly as measurements of kymograph curves. The measurements, with the powers used, are accurate to.01 sec.
The smoked disc records are to be preferred to those scratched with a diamond, because of the superior legibility of the line, an important item if thousands of measurements are to be made. The records are fixed with shellac and preserved, or they may be printed out by a photographic process and the prints preserved. The parallel set of wax records is preserved with them. There are several ways in which the wax records lend themselves to the study of rhythmic questions. It is easy to change the rate, and thereby get new material for judgment, in a puzzling case. Consonant qualities are never strong, and it is easy so to damp the reproducer that only the vowel intensities are heard. The application in the study of rhyme is obvious.
All the series consisted of regular nonsense syllables. The accented and unaccented elements were represented by the single syllable 'ta' ('a' as in father). Rhymes were of the form 'da,' 'na,' 'ga' and 'ka.' In other parts of the work (cf. Table IV.) the vowel o had been used in rhymes for contrast; but the same vowel, a, was used in these records, to make the intensity measurements comparable.
The records of the measurements were as complete as possible. The sonant and the interval of each element were measured, and all the pauses except the stanza pause were recorded. The intensity of each syllable was recorded beneath the length of the syllable, and notes were made both from the appearance of the curve and from the phonograph record.
2. The Normal Form of Unrhymed Verse.
To determine the influence of a subordinate factor in rhythm such as rhyme, it is necessary to know the normal form of verse without this factor. It is natural to assume that the simplest possible form of material would be individual feet recorded seriatim. But on trial, such material turned out to be very complex; the forms changed gradually, iambs becoming trochees and trochees changing into spondees. It is very probable that the normal foot occurs only in a larger whole, the verse.
To corroborate the conclusions from perceived rhythms as to the existence of variations in earlier and later parts of the verse, a table of mean variations was prepared from the material recorded and measured for other purposes.