. Carnegie Institution of Washington publication. . .60 .70 OQ. )0l J 0 0 10 20 3 0 4|0 50 GJQ 7 f>!^^^ . PULSE. CYCLES,. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Carnegie Institution of Washington. Washington, Carnegie Institution of Washington

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Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1919