Page:On the economy of machinery and manufactures - Babbage - 1846.djvu/218

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(236.) Pins, "Elevens," 5,546 weigh one pound; "one dozen" = 6,932 pins weigh twenty ounces, and require six ounces of paper.

(237.) Cost of 12,000 pins, No. 6, each being eight-tenths of an English inch in length,—as they were manufactured in France about 1760; with the cost of each operation: deduced from the observations and statement of M. Perronet.