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This unique research will start on the elastic and other properties of rocks. For example, how do rocks under great pressure conduct heat? This is something fundamental in the study of earth transformations. To prosecute the study Professor Bridgman has some remarkably powerful little machines. They consist essentially of thick, steel-jacketed cylinders carefully cast and precisely machined. The hydraulic pressure which oil puts against pistons in the cylinders is presumably less than the pressure upon things deep within the earth. Yet the man-made pressure changes the nature of elements. Thirty-nine of 48 pure metals which Professor Bridgman has squeezed become better conductors of electricity the greater the pressure. Iron becomes more rigid, glass less rigid. Zinc crystals compress seven times as much in one direction as in another. Most compressible of metals is cesium, presumably because its atom is highly complex. The greater the pressure on rocks, the greater the heat needed to melt them.
Harvard alumni were piqued three weeks ago when the American Physical Society and the Optical Society of America met at Cambridge (TIME, Mar. 7). In the excitement of dedicating Massachusetts Institute of Technology's new spectroscopic laboratory, the visitors paid scant attention to the dedication of the last section of Harvard's group of buildings for the study of Physics. Between the Jefferson Physical Laboratory (Professor Theodore Lyman, director) and the Cruft High Tension Electrical Laboratory (Professor George Washington Pierce, director) with its two 100-ft. wireless towersbetween them was a space, which now has been enclosed by a connecting wing of workrooms.