A Text-book of Electro-Chemistry . By Max Le Blanc, Professor in the University of Leipzig. Translated from the Fourth German Edition by W. R. Whitney, Ph.D., Director of the Research Laboratory of the General Electric Company, and John W. Brown, Director of the Research and Battery Laboratory of the National Carbon Company. 8vo, pp. xiv +338. Price, $2.60 net. New York: The Macmillan Company.