Five double-disk records, each tied to a chapter of the book
Seashore's preface lists the records and the chapters that explain them. They came with a free booklet of directions, norms and interpretations for class experiments, school surveys, music studios, and what he called “scientific entertainment in home circles.” Pick a record.
A second series covered motor tests, using instruments for timed and rhythmic action. Seashore says the first series “will be extended from time to time.”
Is the second tone higher or lower?
Seashore's standard was a′ at 435 vibrations per second, the international pitch of his day. You hear it, then a second tone that differs by a few vibrations. The difference shrinks when you're right and grows when you're wrong, stepping through the same differences as his Table I. After 24 trials the page reads your result off his norms.
Everything in percentile rank
Seashore kept every measurement as a percentile rank, which he called a universal way of putting very different measurements on common terms. Rank 1 is the lowest of a hundred, rank 100 the highest. His pitch table comes from 1,265 university students in or above the sophomore class.
The spread is enormous. The best could hear a quarter of a vibration's difference at 435; the bottom few couldn't reliably hear 34 vibrations, a third of a tone.
A talent profile, not a single number
Forty years of the Seashore tests
- [1]Seashore, C. E. (1919). The Psychology of Musical Talent. Boston: Silver, Burdett and Company (Internet Archive).archive.org
- [2]Seashore, C. E., Lewis, D., & Saetveit, J. G. (1960). Seashore Measures of Musical Talents, revised manual. Psychological Corporation (Internet Archive search).archive.org
- [3]Wikipedia. Carl Seashore.en.wikipedia.org
- [4]Seashore, C. E. (1915). The measurement of musical talent. The Musical Quarterly, 1(1), 129–148.doi
- [5]University of Iowa. Seashore Hall and the Seashore legacy (university archives search).search
Editorial record: title page, the five records, the percentile method, Table I, the Theodora profile and the brightness comparison are from the digitised 1919 first edition [1]. The 1939 revision, 1960 manual and biographical dates are from secondary sources and weren't checked against the originals.