Mechanical Amalgamation: Progress Report of Research On Dental Materials**Cooperative research by the National Bureau of Standards and the American Dental Association.Publication approved by the Director of the Bureau of Standards of the U. S. Department of Commerce.Read before the Section on Histology, Physiology, Pathology, Bacteriology and Chemistry (Research) at the Seventieth Annual Session of the American Dental Association, Minneapolis, Minn., Aug. 22, 1928.