When we reviewed the geophysical activity of 1949 at our meeting last year, we looked back on a considerable decline in the United States from a high of 520 seismograph crew-months in November, 1948 to a low of 416 in February, 1950, the last month for which information was then available. We did not know at the time whether the decline would continue and, if so, how far. The atmosphere was one of concern. We noted, however, that economic and other factors strongly indicated an early reversal and the future surpassing of earlier peaks.

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