03 July 1964
Vol 145, Issue 3627

About The Cover

Facimile of the seismogram of the Alaskan earthquake which was made by the visible recording instrument at the U.S. Department of Commerce, approximately 48 hours. Each horizontal line represent 1 hour and the veritcal lines occur at 1-minute intervals. The preliminary wave of the main shock arrived in Washington at 03 hr 44' 46" U.T., 28 March (white arrow). The computed time of orgin in Alaska was 03 hr 36' 13" U.T., 28 March. See page 74. [U.S. Department of Commerce]