Scientific American Supplement, No. 531, March 6, 1886   By: Various

SCIENTIFIC AMERICAN SUPPLEMENT NO. 531

NEW YORK, MARCH 6, 1886

Scientific American Supplement. Vol. XXI, No. 531.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.

TABLE OF CONTENTS.

I. CHEMISTRY AND METALLURGY. Annatto. Analyses of the same. By WM. LAWSON

Aluminum. By J.A. PRICE. Iron the basis of civilization. Aluminum the metal of the future. Discovery of aluminum. Art of obtaining the metal. Uses and possibilities

II. ENGINEERING AND MECHANICS. The Use of Iron in Fortification. Armor plated casements. The Schumann Gruson chilled iron cupola. Mougin's rolled iron cupola. With full page of engravings

High Speed on the Ocean

Sibley College Lectures. Principles and Methods of Balancing Forces developed in Moving Bodies. Momentum and centrifugal force. By CHAS.T. PORTER. 3 figures

Compressed Air Power Schemes. By J. STURGEON. Several figures

The Berthon Collapsible Canoe. 2 engravings

The Fiftieth Anniversary of the Opening of the First German Steam Railroad. With full page engraving

Improved Coal Elevator. With engraving

III. TECHNOLOGY. Steel making Ladles. 4 figures

Water Gas. The relative value of water gas and other gases as Iron reducing Agents. By B.H. THWAITE. Experiments. With tables and 1 figure

Japanese Rice Wine and Soja Sauce. Method of making

IV. ELECTRICITY, MICROSCOPY, ETC. Apparatus for demonstrating that Electricity develops only on the Surface of Conductors. 1 figure

The Colson Telephone. 3 engravings

The Meldometer. An apparatus for determining the melting points of minerals

Touch Transmission by Electricity in the Education of Deaf Mutes. By S. TEFFT WALKER. With 1 figure

V. HORTICULTURE. Candelabra Cactus and the California Woodpecker. By C.F. HOLDER. With 2 engravings

How Plants are reproduced. By C.E. STUART. A paper read before the Chemists' Assistants' Association

VI. MISCELLANEOUS The Origin of Meteorites. With 1 figure

THE USE OF IRON IN FORTIFICATION.

Roumania is thinking of protecting a portion of the artillery of the forts surrounding her capital by metallic cupolas. But, before deciding upon the mode of constructing these formidable and costly affairs, and before ordering them, she has desired to ascertain their efficacy and the respective merits of the chilled iron armor which was recently in fashion and of rolled iron, which looks as if it were to be the fashion hereafter.

[Illustration: FIG. 1. MOUGIN'S ROLLED IRON TURRET.]

The Krupp works have recommended and constructed a cupola of casehardened iron, while the Saint Chamond works have offered a turret of rolled iron. Both of these recommend themselves by various merits, and by remarkably ingenious arrangements, and it only remains to be seen how they will behave under the fire of the largest pieces of artillery.

[Illustration: FIG. 2.]

We are far in advance of the time when cannons with smooth bore were obliged to approach to within a very short range of a scarp in order to open a breach, and we are far beyond that first rifled artillery which effected so great a revolution in tactics.

[Illustration: FIG. 3.]

To day we station the batteries that are to tear open a rampart at distances therefrom of from 1,000 to 2,000 yards, and the long, 6 inch cannon that arms them has for probable deviations, under a charge of 20 pounds of powder, and at a distance of 1,000 yards, 28 feet in range, 16 inches in direct fire and 8 inches in curved.