Scientific American Supplement, No. 787, January 31, 1891   By: Various

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 insurance of lives, with tables and calculations

VI. MATHEMATICS. The Trisection of Any Angle. By FREDERIC R. HONEY, Ph.B. A very ingenious demonstration of this problem, based on the properties of conjugate hyperbolas

VII. METEOROLOGY. Note on the Mt. Blanc Meteorological Station

The Flood at Karlsbad. Account of the recent flood and of its destructive effects. 1 illustration

VIII. MECHANICAL ENGINEERING. Station for Testing Agricultural Machines. A proposed establishment for applying dynamometer tests to agricultural machines. 1 illustration

Steam Engine Valves. By THOMAS HAWLEY. A review of modern slide valve practice, the lap, cut off, and other points. 6 illustrations

IX. MISCELLANEOUS. Science in the Theater. Curious examples of stage effect in fictitious mesmerizing and hypnotizing. 4 illustrations

Theatrical Water Plays. Recent episodes in real water plays at Hengler's Circus, London. 2 illustrations

X. NAVAL ENGINEERING. The French Ironclad War Ship Colbert. An armored wood and iron ship, with central battery. 1 illustration

XI. PHYSIOLOGY AND HYGIENE. Newer Physiology and Pathology. By Prof. SAMUEL BELL. M.D. An excellent presentation of modern practice in the light of bacteriology

Test Card Hints. How to test the eyes for selecting eyeglasses and spectacles

The Composition of Koch's Lymph. What Prof. Koch says it is and what it can do. The cabled account of the disclosure so long waited for

XII. TECHNOLOGY. Firing Points of Various Explosives. The leading explosives, with the temperature of their exploding points tabulated

The Recovery of Gold and Silver from Plating and Gilding Solutions A paper of interest to silver and gold platers, as well as photographers

Water Softening and Purifying Apparatus. An apparatus for treatment of sewage, etc., chemically and by deposition. 1 illustration

THE FRENCH IRONCLAD WAR SHIP COLBERT.