IN a previous letter to NATURE (July 20, 1911, p. 78) the hypothesis was proposed that the atomic weight being equal to about twice the intra-atomic charge, “to each possible intra-atomic charge corresponds a possible element,” or that (Phys. Zeitschr., xiv., 1912, p. 39), “if all elements be arranged in order of increasing atomic weights, the number of each element in that series must be equal to its intra-atomic charge.”

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