THERE is a well-known saying, variously attributed to the great King Solomon and other sages of antiquity, to the effect that "there is nothing new under the sun." The inventive genius of man, as far as it is personified in the metallurgist, has often had the truth of this statement poignantly brought to mind when investigating the priority of ideas in its own particular branch of science. Not infrequently some operation, at first innocently taken for a novel procedure, has later been found to have had an irrefutable precedent in the more or less remote past. When confronted by a question of this kind the metallurgist can generally much simplify his search if he at once turns his scrutinizing gaze towards that ancient home of metallurgy, Germany. Vast departments of the smelting art have originated there, and even when Germany has not been in position to claim priority of invention, it has at least been characterized by a distinction equally as worthy-i.e., that of the faithful and authoritative exposition of the theoretical grounds on which the invention rests.