As for my own experiments, my Department of Volcanology at the University was moved into a concrete basement room a thousand square feet in area in the Home Economics building, and the expense was shared with the Hawaiian Volcano Research Association. Here I had office and shop and collections of the Research Association, and the assistance of a secretary and a junior researcher who is an instrument maker. Thus were assembled in a fire resistant location my petrographic and mineral collections from Europe, the Caribbean, Central America, and the Pacific lands, together with manuscripts from my days of Harvard and Massachusetts Tech to the middle of the century and classified accumulations of my Navy monographs, lantern slides, negatives, photographs, maps, drawings, correspondence, and instruments, including material obtained by the Research Association for experiments still continuing on the hardness of minerals. One objective of this hardness measurement was an instrument for machine shops which would give in half a minute the length of a standard scratch made by a standard dental disk of silicon carbide. I called this the “Jaggar Scratch Tester” and Mr. Paul Rushforth, a Honolulu optician, made improved models of the instrument. When a book was published on the experiments with some three hundred woods, minerals, metals, and plastics, Dr. Grodzinski of the commercial diamond establishments in London became interested and reproduced the paper in a review dealing with industrial diamonds, which have become of great importance in the world of grinding machinery. This made a new contact with England, similar to that made by Boynton with my microsclerometer in 1908, when he applied it to the microscopic constituents of steel under the British Iron and Steel Institute. I sent a copy of my new report to the Pearl Harbor industrial laboratory, along with one of the instruments. Endorsers of this report were Mr. W. H. Hammond and Dr. Earl Ingerson, director of the mineral laboratories of the U.S. Geological Survey. A result of the experiments on hardness is the knowledge that the important quality is softness, or abradability, and speed of removal of material in any uniform mechanical cutting process. It was formerly thought that the big intervals in values were between the hard substances. It turns out that the biggest gaps in value are in soft substances like coals and clays and plasters. Hardness is purely a negative quality of resistance, and measurements are of yielding, not of resisting.