first edition Softcover
by Wright, F.E.
First Edition. Softcover. 8vo, paged -540, graphs; VG; tan cover with black print, pencil notations at top edge, bump to lower right corner with creasing throughout; back cover has blue library stamp at bottom edge; pages have slight creasing and curling along right edge, slight smudge at right page edge of p. 537, otherwise clean interior; "Reprinted from the Proceedings of the National Academy of Sciences, Vol. 13, No. 7, pp. 535-540, July 1927"; Papers from the Geophysical Laboratory, Carnegie Institution of Washington, No. 647." 1293167. Rockville Non-Retail Listings. (Inventory #: 1293167)