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SCIENTIFIC AMERICAN SUPPLEMENT NO. 303

NEW YORK, OCTOBER 22, 1881

Scientific American Supplement. Vol. XII, No. 303.

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. ENGINEERING AND MECHANICS.--New Eighty-ton Steam Hammer at the Saint Chamond Works, France.--7 figures.--Elevation of hammer.--Profile-- Transverse section.--Profile view of foundation, etc.--Plan of plant.--General plan of the forging mill.--Details of truss and support for the cranes.

Great Steamers.--Comparative details of the Servia, the City of Rome, the Alaska, and the Great Eastern.

Improved Road Locomotive.--2 figures.--Side and end views

American Milling Methods. By ALBERT HOPPIN.--Ten years' progress.--Low milling.--Half high milling.--High milling.--Important paper read before the Pennsylvania State Millers' Association.

Machine for Dotting Tulles and other Light Fabrics.--3 figures.

II. TECHNOLOGY AND CHEMISTRY.--The Reproduction and Multiplication of Negatives. By ERNEST EDWARDS.

A New Method of Making Gelatine Emulsion. By W. K. BURTON.

The Pottery and Porcelain Industries of Japan.

Crystallization Table.

The Principles of Hop Analysis. By Dr. G. O. CECH.

Water Gas.--A description of apparatus for producing cheap gas, and some notes on the economical effects of using such gas with gas motors, etc.--By J. EMERSON DOWSON.

On the Fluid Density of Certain Metals. By Professors CHANDLER ROBERTS and T. WRIGLESON.

III. PHYSICS, ELECTRICITY, ETC.--Electric Power.--The nature and uses of electricity.--Electricity vs. steam.

On the Method of Obtaining and Measuring Very High Vacua with a Modified Form of Sprengel Pump. By Prof OGDEN N. ROOD.--4 figures.-- Apparatus for obtaining vacua of one four hundred-millionth of an atmosphere--Construction.--Manipulation.--Calculations.--Results

IV. ART, ARCHITECTURE, ETC.--Old Wrought Iron Gates, Guildhall. Worcester, England. 1 figure.

The French Crystal Palace, Park of St. Cloud, Paris. 1 full page illustration.

Suggestions in Architecture. A Castellated Chateau. Perspective and plan. Chateau in the AEgean Sea.

V. HYGIENE AND MEDICINE.--Hydrophobia Prevented by Vaccination.

On Diptera as Spreaders of Disease. By J. W. SLATER.

On the Relations of Minute Organisms to Certain Specific Diseases.

VI. ASTRONOMY--The Centenary of the Discovery of Uranus. By F. W. DENNING. 2 figures. Approximate place of Uranus among the stars at its discovery, March l3, 1871.--Orbits of the Uranian Satellites.

VII. BIOLOGY, ETC.--The Varying Susceptibility of Plants and Animals to Poisons and Disease.

Kind Treatment of Horses.

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NEW EIGHTY TON STEAM HAMMER AT THE SAINT CHAMOND WORKS

Ever since the improvements that have been introduced into the manufacture of steel, and especially into the erection of works for its production, have made it possible to obtain this metal in very large masses, it has necessarily been preferred to iron for all pieces of large dimensions, inasmuch as it possesses in the highest degree that homogeneousness and resistance which are so difficult to obtain in the latter metal. It has consequently been found necessary to construct engines sufficiently powerful to effect the forging of enormous ingots, as well as special furnaces for heating them and apparatus for manipulating and transporting them.

The greatest efforts in this direction have been made with a view to supplying the wants of heavy artillery and of naval constructions;