The present book was written for three classes of readers-"college students, technically trained men who deal with processes requiring high temperature measurements, and less trained observers who may make the measurements." The book is practically a synopsis of "Measurement of high temperatures" by Burgess and Le Chatelier, Wiley, 1912, but is presented in different form especially suitable for the class room, as minor details are omitted, and in several places the text is illustrated by practical problems. Also at the end of each chapter are several experiments, fourteen in all, which are prepared in sufficient detail for the ordinary student, and which cover the field of pyrometry very satisfactorily. The chapters are headed as follows: (1) Standard Temperature Scales; (2) Resistance Pyrometry; (3) Thermoelectric Pyrometry; (4) Radiation Pyrometry; (5) Optical Pyrometry. The text is well illustrated and several new American instruments are shown.