reason is that enough guns are not always brought into action and fired simultaneously, but there may be also minor reasons. He inserts an estimate of the cost of two experiments in which two hundred siege-guns should be used, making the amount $160,000 for the two. After this mode of causing precipitation had become systematized, he estimates that "a good rain-storm" would cost less than $21,000.
The Septonate and the Centralization of the Tonal System. By Julius Klauser. Milwaukee: William Rohlfing & Sons. Price, $3.
It is no exaggeration of the condition of an average musical student that Mr. Klauser describes in the introduction to this work. After pursuing the study of music for ten, fifteen, or twenty years, he may still be unable "to tell you what the intervals, chords, rhythms, and meters are that you dictate for oral discrimination." He has learned to use his voice or some instrument. His eye, hand, or vocal organs may be trained, but the cultivation of his ear has been left to chance. "Students are not taught, nor do they learn, to hear." A system of teaching which turns out pupils ignorant of the elements of their art, and liable to be embarrassed by simple questions, must be faulty. The author of this volume holds that there are two fundamental errors in musical training: one, the inverse method of instruction, in which a pupil is taught to perform before he can listen intelligently; the other, the usual presentation of the tonal system. As a remedy for the first, the beginner should be taught to hear exactly and discriminate from the start. A corrective for the second demands a reconstruction of our tonal conceptions. "The scale is too complex a unit; . . . . its combinations are too multiple for any beginner to grasp as a whole." After much investigation of tonal relations and analysis of the mental process of musical reproduction, Mr. Klauser has fixed upon the scale-half or tetrachord, and the union of two scale-halves with a common central tonic, as simpler elements for tone-study. To the latter group of tones he gives the name of septonate, "seven principal tones in their natural positions," three preceding and three following a tonic. Other divisions of tones, which are the framework of the system, are the key-group and the tone-stratum. The key-group contains seventeen tones, consisting of the septonate and ten other tones; five sharps, called up-mediates, and five flats, the down-mediates. Ten more tones, named secondary intermediates, added to the key-group, complete the tone-stratum. A new theory for tone discrimination is introduced in the Principle of Progression. In hearing a series of tones, "we are disposed to progress on certain tones and to stop on others." The tones from which we feel a desire to move are called by-tones; those which create a feeling of rest are harmonics. The author explains these phenomena as the result of the antagonism or agreement which certain tones have with the melodic phrase already in mind, and which he calls "the governing voice."
The author argues the need of a new notation, and may hereafter attempt that Sisyphean task. Prefixed to this volume is an interesting and suggestive essay on a higher education in music. Some experiences in training children deficient in tonesense deserve attention. The relation of music and mind is exhibited in the fact that music must be executed in a prescribed tempo—"the moments of cognition are limited." So "a concentrative power without parallel" is cultivated. In concluding the volume, various views of the origin of music are given, the author believing that music antedates speech, as the chromatic intervals of the wind and the melodious phrases of birds preceded the existence of man.
Elements of Crystallography. By George H. Williams, Associate Professor in the Johns Hopkins University. New York: Henry Holt & Co. Pp. 250. Price, $1.25 net.
This text-book, which is offered to students of chemistry, physics, geology, and mineralogy, contains as much of the subject as any one who does not intend to make mineralogy his life-work will need to know. It describes the several crystallographic systems, taking up a considerable number of the combinations possible under each, and giving diagrams and symbols. There are also chapters on Crystal Aggregates and Imperfections of Crystals, and an Appendix on Zones, Projection, and the Construction of Crystal Figures. To the student of miner-
