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New subscriptions will be entered from the time the order is received; but the back numbers of either the Scientific American or the Scientific American Supplement will be sent from January when desired. In this case, the subscription will date from the commencement of the volume, and the latter will be complete for preservation or binding.


VOL. XXXVII., No. 2. [NEW SERIES.] Thirty-second Year.


NEW YORK, SATURDAY, JULY 14, 1877.


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