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TABLE OF CONTENTS.
PAGE
I.CHEMISTRY AND METALLURGY.—[Preparation of Chlorhydrines][6452]
[Chemical Compounds Made by Compression. By M. W. Spring.][6452]
[Copper Alloys among the Ancients. By Prof. E. Reyer.]—A valuable and important paper, full of useful information, showing the geology of the metals.—[Characteristics of copper alloys,] with tables showing constituents used in different countries.—[Casting the alloys.]—Hard bronze of the ancients.—[Summary of alloys used by the ancients][6452]
II.ENGINEERING AND MECHANICS.—[Bietrix's Vertical and Compound Engine.]—With description and numerous figures[6439]
[Improved Gas Engine.]—With [engraving][6440]
[Meters for Power and Electricity. By M. C. Vernon Boys.]—A valuable and instructive paper.—Showing the object of meters, the way in which some of them are made, and their manner of operating.—Several figures[6440]
[Raising and Moving Masonry Buildings.]—With full page of engravings, illustrating various examples of large buildings composed of masonry that have been moved and raised[6443]
III.TECHNOLOGY.—[Filter for Industrial Works.]—Showing how to make and use the filter.—With [engraving.][6443]
[The Val St. Lambert Glass Works.]—With full description and two illustrations.[6444]
[Proper shoeing.]—Horses' feet should be treated in accordance with the work expected of them.[6444]
[Ideas.—Relating to Milling. By A Looker-on.][6445]
[Photographs for Studying the Movements of Men and Animals. By M. Marey.]—How to avoid confusion in photographing rapid movements.—With [diagram.][6445]
[Detective Photography.]—As applied to criminal cases.[6445]
[Strength of Yellow Pine.][6449]
IV.ARCHITECTURE.—[English Lodges.]—With engraving.[6447]
[The Decay of the Building Stones. By Dr. A. A. Julien.]—[The building stones, their varieties, localities, and edifices constructed of each.]—[Durability of building stones in New York and vicinity.]—[Methods of trial of building stone.]—[Means of protection and preservation of stone.][6447]
V.ELECTRICITY.—[The History of the Electric Telegraph.]—First use of the Volta pile in telegraphy.—Description of Soemmering's apparatus.—With two engravings.[6446]
[A New Sulphate of Copper Pile.]—With [engraving.][6446]
VI.MEDICINE AND HYGIENE.—[Filth Diseases in Rural Districts.]—Showing why there is greater danger of poisoning from sewage in the country than in the city.—Several examples showing apparent causes and consequences.—How is the infection carried?[6450]
[The Physiology of Sleep.]—Giving different theories.[6451]
[A New Method for the Detection of Sugar in the Urine.][6452]
VII.MISCELLANEOUS.—[Elephants Moving Timber at Moulmein, Burmah.]—With [engraving.][6449]
[The Education of German Women.][6449]
[Horse Medicine Bit.]—With two engravings.[6451]
[The Big Trees of California.][6454]
[Science in Antiquity.—Heron's Pneumatic and compressing apparatus.]—With two engravings.[6450]

PATENTS.

In connection with the Scientific American, Messrs. Munn & Co. are Solicitors of American and Foreign Patents, have had 38 years' experience, and now have the largest establishment in the world. Patents are obtained on the best terms.