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628 to admit that one principal object which he kept before his mind in the preparation of the book, was to show the inadequacy and unsatisfactoriness of a prevailing system of psychology which may be indicated by the word phenomenalism." By phenomenalism we suppose he means corporealism, or the psychology which takes organic conditions into account in studying mental effects. But he "shows the inadequacy" of that method chiefly by ignoring it, and if disembodied spirits want a text-book of psychology adapted to their circumstances, the present work may be recommended to them as so well suited that it would not need revision to free it of any sublunary dross.

elegantly-printed little volume, with an attractive title, which is suggestive of a most interesting class of scientific questions. But the contents of the book are sorely disappointing. The questions we expected to meet are not considered, and the little science there is is bad. In a chapter devoted to "The Nature and Origin of Sound," the current physical explanation of the phenomena is rejected, and a sonorous or musical fluid is resorted to. The author says: "Why do not all the extended cords of a musical instrument, such as a piano, violin, violoncello or guitar, repeat together the tone or cry of the voice which utters sounds above them? Why, of all the cords of the same instrument, do those only which are in unison with this voice produce sound? Did not the noise, the sound, the sonorous wave, as they choose to call it, which escapes from the mouth, strike, disturb, and agitate all the strings? Yes, but the sonorous fluid did not find all of these its Leyden jar, nor in any the capacity for being charged with the sonorous fluid. This, I think, is the explanation of the phenomenon that can never be explained by the theory of the molecular vibration of the bodies, or of the undulations of the air." Where such crude notions are entertained, we cannot expect a very refined analysis of the relations of music to the nervous system; nevertheless, the volume contains a good deal of information in which the lovers of music may be interested.

is a very valuable little hand-book for the student of practical mineralogy, and an immense amount of careful and accurate information has been condensed into its pages. It grew out of the necessities of practical teaching in the school of Freiberg, and has been revised and adapted for use in this country by an experienced American geologist, and it is a guide to practical work which every student of minerals will find indispensable. The method of study to which it is tributary is thus indicated in a passage from the translator's introduction:

"Every one who has had the good fortune to study at the Royal Saxon Mining Academy, in Freiburg, will bear witness to the efficacy of the system there pursued for instructing young students in the art of distinguishing mineral species on the spot, by the aid of a tolerable memory, and an intelligent observation of a few of their most striking physical properties—both brought to the highest point of perfection of which they are capable by judicious cultivation, and kept in their best condition by assiduous daily exercise.

"The method of practical instruction pursued there, and which has been introduced by Freiberg graduates into many schools in this country, requires merely a cabinet of unlabeled minerals, and a professor who can determine—not one who has learned them. Each student, of a class of ten or more, places a tray of such minerals before him, and occupies the two hours devoted to "Praktische Uebung" in discovering, by the aid of the knife, the streak-tablet, the file, and the magnifying-glass,