The Project Gutenberg EBook of Scientific American Supplement, No. 787,
January 31, 1891, by Various

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Title: Scientific American Supplement, No. 787, January 31, 1891

Author: Various

Release Date: November 10, 2004 [EBook #14009]

Language: English

Character set encoding: ASCII

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[Illustration]

SCIENTIFIC AMERICAN SUPPLEMENT NO. 787

NEW YORK, January 31, 1891

Scientific American Supplement. Vol. XXXI., No. 787.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.

* * * * *

TABLE OF CONTENTS.

I. BIOGRAPHY.--CHARLES GOODYEAR.--The life and discoveries of
the inventor of vulcanized India rubber, with portrait.--1
illustration

II. BIOLOGY.--Can we Separate Animals from Plants?--By ANDREW
WILSON.--A debated point well discussed.--The bases on which
distinctions must be drawn

III. ELECTRICITY.--A New Electric Ballistic Target.--A target
for investigations of the velocity of projectiles, now in use at
the United States Military Academy, West Point, N.Y.--1
illustration.

Electric Erygmascope.--An electric lighting apparatus for
examining earth strata in bore holes for geologists' and
prospectors' use.--1 illustration

The Electro-Magnet.--By Prof. SILVANUS THOMPSON.--Continuation
of this exhaustive treatise, giving further details on special
points of construction.--1 illustrations

IV. ENTOMOLOGY.--Potash Salts.--The use of potash salts as
insecticides, with accounts of experiments

The Outlook for Applied Entomology.--By Dr. C.V. RILEY, U.S.
entomologist.--The conclusion of Prof. Riley's lecture, treating
of the branch of entomology with which his name is so honorably
associated

V. INSURANCE.--The Expense Margin in Life Insurance.--Elaborate
review of the necessary expenses of conducting the