GEOCHRONOLOGY, AS BASED ON SOLAR RADIATION, AND ITS RELATION TO ARCHEOLOGY.

pp687-696, drawings, short bibliography. Removed from ANNUAL REPORT OF THE BOARD OF REGENTS OF THE SMITHSONIAN INSTITUTION, FOR THE YEAR ENDING JUNE 30, 1928. VG. In report covers. From the introduction: "In the American Journal of Science for 1920 mention was made of my plan for investigating certain laminated clays in North America. During a previous visit to that country in 1891 I had noticed, in several places, laminated clays, similar to late glacial melting sediments in Sweden; these I had found, by long continued investigations, to represent the annual deposit from the melting water along the border of the retreating ice edge.I thus succeeded in tracing, step by step, the recession of the ice edge and the immediately following progress of the clay varves over one region after the other, until the whole line from the south to the center of Sweden had been traced.".