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SCIENTIFIC AMERICAN SUPPLEMENT NO. 392




NEW YORK, JULY 7, 1883

Scientific American Supplement. Vol. XVI, No. 392.

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.   ELECTRICITY AND MAGNETISM.--Improved Dynamo Machine.
     Eight figures.

     An Improved Manganese Battery.--By GEO. LEUCHS.

     The Cause of Evident Magnetism in Iron, Steel, and other Magnetic
     Metals.--By Prof. D. E. HUGHES. Neutrality.--Superposed
     Magnetism.--Elastic Nature of the Ether Surrounding the Magnetic
     Molecules. 3 figures.

II.  ENGINEERING.--The Westinghouse Brake. 2 figures.

     Hydraulic Elevators and Motors.--By B. F. JONES.--Bearing
     upon the Water Supply of Cities.--Cost of Water used.--Objectionable
     effects on Water Works.--Best method of arranging water
     supply.--Cause of Accidents.--Advantages of Water Motors over
     Steam Engines.--Rates for Water Motors.

     Water Supply of Small Towns.--Process of Softening Hard
     Water. Six figures.

     Improved Water Meter. Several figures.

III. TECHNOLOGY.--Washing Machine for Wool. 1 figure.

     Increasing the Illuminating Power of Gases, etc.--By V. POPP.--
     3 figures.

     Preventing Iron from Rusting.

     An Elastic Mass for Confectioners' Use.

     Caoutchouc.

     Phot