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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