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SCIENTIFIC AMERICAN SUPPLEMENT NO. 401

NEW YORK, SEPTEMBER 8, 1883

Scientific American Supplement. Vol. XVI, No. 401.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.

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TABLE OF CONTENTS.

I. CHEMISTRY.--On the Different Modifications of Silver Bromide and Silver Chloride.

Analysis of New Zealand Coal.

On the Determination of Manganese in Steel, Cast Iron, Ferro-manganese, etc.

Manganese and its Uses.

Ozokerite or Earth-wax. By WILLIAM L. LAY. A valuable and instructive paper read before the New York Academy of Sciences.--Showing the nature, sources, and applications of this remarkable product.

On the Constitution of the Natural Fats.

II. ENGINEERING AND MECHANICS.--Improved Spring wheel Traction Engine.--With two engravings.

An Improved Iron Frame Gang Saw Mill.--With one large engraving.

The Heat Regenerative System of Firing Gas Retorts.--Siemens' principle.--As operated at the Glasgow Corporation Works.--With two engravings.

A New Gas Heated Baker's Oven.

III. TECHNOLOGY.--How to Produce Permanent Photographic Pictures on Terra Cotta, Glass, etc.--With recipes and full directions.

How to Make Paper Photo Negatives.--Full directions.

Some of the Uses of Common Alum.

An Improved Cloth Stretching Machine.--With an engraving.

Purification of Woolen Fabrics by Hydrochloric Acid Gas.

Apparatus for Preventing the Loss of Carbonic Acid in Racking Beer.--With an engraving.

IV. ELECTRICITY.--Application of Electricity to the Bleaching of Vetable Textile Materials.--With figure of apparatus.

Table Showing the Relative Dimensions, Lengths, Electrical Resistances, and Weights of Pure Copper Wires.

V. ASTRONOMY.--The Solar Eclipse of 1883.--An interesting abstract from a report of C. S. HASTINGS (Johns Hopkins University), of the American Astronomical Exhibition to the Caroline Islands.

VI. NATURAL PHILOSOPHY.--Recent Experiments Affecting the Received Theory of Music.--An interesting paper descriptive of certain experiments by President Morton, of Stevens Institute.

The Motions of Camphor upon Water.--With an engraving.

VII. ARCHITECTURE.--Suggestions in Village Architecture.-- Semidetached villas.--Bloomfield crescent.--With an engraving.

Specimens of Old Knocking Devices for Doors.--Several figures.

VIII. ARCHAEOLOGY.--A Buried City of the Exodus.--Being an account of the recent excavations and discoveries of Pithom Succoth, in Egypt.--With an engraving.

The Moabite Manuscripts.

IX. AGRICULTURE. HORTICULTURE, ETC.--The Queen Victoria Century Plant.--With an engraving.

Charred Clover.

A New Weathercock.--With one figure.

X. MISCELLANEOUS.--New Monumental Statue and Landing Place in Honor of Christopher Columbus at Barcelona, Spain.--With an engraving.

Scenery on the Utah Line of the Denver and Rio Grande Railway.

Captain Matthew Webb.--Biographical sketch.--With portrait.

The Dwellings of the Poor In Paris.

Shipment of Ostriches from Cape Town, South Africa.--With one page of engravings.

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MONUMENT TO CHRISTOPHER COLUMBUS, AT BARCELONA, SPAIN.

The cultivated and patriotic city of Barcelona is about to erect a magnificent monument in honor of Columbus, the personage most distinguished in the historic annals of all nations and all epochs. The City of Earls does not forget that here the discoverer of America disembarked on the 3d of April, 1493, to present to the Catholic monarchs the evidences of the happy termination of his enterprise. In