That is to say, there are but three persons in a hundred who, having just sung the tone which is produced by a tuning fork vibrating two hundred and fifty-six times per second, can then voluntarily and accurately change the pitch of the voice to represent the tone of a fork vibrating 256.9 times per second, a change of .9 of a vibration. But fifty persons of the hundred can produce voluntarily a change of three vibrations, and ninety-two of the hundred can produce the very large change of nine vibrations. Seashore, of course, points out that in addition to these various measurements, "there must be other measurements, statistical data, biographical information, and free observations concerning musical training, traits of temperament and attitude, spontaneous tendencies in the pursuit of music, general education and non-musical accomplishments, social circumstances and physique," and that all these in their unity must be considered in the light of expert knowledge and expert technical insight before they can be said to give an adequate estimate of the particular individual's various capacities and qualifications as a singer. Those interested in the use of psychological tests in connection with musical ability should familiarize themselves with the many original reports from Seashore's laboratory. The methods there being followed may well serve as models for future analyses of vocational demands and individual tests. If the highly specialized work of singing calls for such complex analysis and for such varied measurements, technical skill, and arduous collection of norms and standards, one realizes the utter folly of such vocational counsel as that which vaguely recommends the candidate to "be a musician," "be a writer," etc. Indeed, we may now begin to see that it is only when each particular aspect of each particular calling is thoroughly analyzed into its elementary requirements, when reliable tests for the detection and measurement of these abilities are available, and adequate norms and standards accumulated in each case, only then can the method of the vocational psychograph come to have practical application in vocational analysis and guidance. How far, we may now ask, has such analysis been able, as a matter of fact, to proceed with the representative types of work? So far as recorded enterprise is concerned there have been three different ways of attempting such analyses. One of these methods is that used by the various vocational bureaus in endeavoring to learn what type of individual is most in demand in the different occupations. Futile as these endeavors have been, it is nevertheless well to have them before us for our future reference and guidance. In the main the questionnaire method has been used in this connection; employers have been asked to state, in much their own way, the necessary or desirable mental and moral qualifications of those who might expect to succeed in the various kinds of work.