SCIENTIFIC AMERICAN

A WEEKLY JOURNAL OF PRACTICAL INFORMATION, ART, SCIENCE, MECHANICS, CHEMISTRY, AND MANUFACTURES.

NEW YORK, MARCH 29, 1879.

Vol. XL., No. 13. [New Series.]

$3.20 per Annum. [POSTAGE PREPAID.]

Scientific American.

ESTABLISHED 1845.

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VOL. XL., No. 13. [New Series.] Thirty-fourth Year.

NEW YORK, SATURDAY, MARCH 29, 1879.

Contents.

(Illustrated articles are marked with an asterisk.)