Scientific American Supplement, No. 275, April 9, 1881

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notes

1

A lecture by Dr. O. J. Lodge, delivered at the London Institution on December 16, 1880.

2

A paper lately read before the Institution of Mechanical Engineers.

3

Read before the Philadelphia County Medical Society, May 12, 1880, by W. G. A. Bonwill, M.D., D.D.S., Philadelphia.