The term elemental should be used with caution because we never encounter a purely elemental state or process. Even in the very simplest form they are merely more or less specific phases of the mental organism; and at any level at which they are observable they probably involve environmental accretions. It is the old story: We never experience pure sensation but meaningful perception. Yet under the most careful experimental control the identification of such specific functions may be reasonably reliable and have considerable validity. Adequate measurements of the sense of timbre are new and therefore have not been employed extensively up to date. But the sense of pitch, the sense of time, and the sense of loudness, together with the sense of rhythm and immediate tonal memory, have been used extensively. The significance of such measurements depends upon the rigidity of the scientific technique and the selection of subjects for experiment. Reliable measurements have been made on a variety of groups and for different purposes more or less related to the problem of inheritance. Studies have been made upon musically precocious children to determine to what degree they were gifted in each of these capacities. All the available blood relatives of six of the foremost musical families in America and a number of such families in European countries have been investigated. These capacities have been measured in selected virtuosi in various fields of music. The measurements have been used for the determination of qualifications for musical organizations and for the analysis of admissions to music schools. Simplified forms of the measurements have been made upon very young children in musical families. Numerous cases of failure in musical education have been investigated and often explained on the basis of presence or absence of these basic capacities. Surveys have been made on groups representing highly-privileged or under-privileged children in the matter of musical facilities. Some of these measures are now a part of the standard tests and measures administered in the public schools so that comparisons can be made with blood relatives, and data are becoming cumulative for scientific comparison of successive generations. Numerous racial studies have been made on a large scale, comparing these capacities, for example, in different degrees of race mixture--as in the transition from pure blacks through mulattoes to whites in a large Negro community, or the comparison of racial groups in Hawaii, the school children in different European countries, Indians with whites, and distinctive races and primitive peoples in different parts of the world.