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SCIENTIFIC AMERICAN SUPPLEMENT NO. 447




NEW YORK, JULY 26, 1884

Scientific American Supplement. Vol. XVIII, No. 447.

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.--The Bitter Substance of Hops.--By Dr. H. BUNGENER.
      --What gives hops their bitter taste?--Processes for obtaining
      hop-bitter acid.--Analysis of the same.

II.   ENGINEERING AND MECHANICS.--Improvements in the Harbor
      of Antwerp.--With engraving of caisson for deepening the
      river.

      Progress of Antwerp.--Recent works in the harbor.

      Bicycles and Tricycles.--By C.V. BOYS.---Advantages of the
      different machines.--Manner of finding the steepness of a hill
      and representing same on a map.--Experiments on ball bearings.--
      The Otto bicycle.

      The Canal Iron Works, London.

      Marinoni's Rotary Printing Press.--With 2 engravings.

      Chenot's Economic Filter Press.--With engraving.

      Steel Chains without Welding.--Method and machines for making
      same.--Several figures.

III.  TECHNOLOGY.--Some Economic Processes connected with the
      Cloth Making Industry.--By Dr. WM. RAMSAY.--How to save and
      utilize soap used in wool scouring.--To recover the indigo from
      the refuse.--Extraction of potash from _suint_.--Use of
      bisulphide of carbon.

IV.   PHYSICS. ELECTRICITY, ETC.--Thury's Dynamo Electric Machine.
      --5 figures.

      Breguet's Telephone.

      Munro's Telephonic Experiments.--9 figures.

      Apparatus for Maneuvering Bichromate of Potassa Piles from a
      Distance.--2 figures.

      Magnetic Rotations.--By E.L. VOICE.--1 figure.

      Lighton's Immersion Illuminator.--1 figure.

      Foucault's Pendulum Experiments.--By RICHARD A. PROCTOR.
      --4 figures.

V.    ARCHITECTURE, ART, ETC.--St. Paul's Vicarage, Forest Hill,
      Kent.--2 engravings.

      Designs for Iron Gates.--An engraving.

VI.   ASTRONOMY.--A New Lunarian.--By Prof. C.W. MACCORD.
      --With 3 figures.

VII.  GEOLOGY.--Coal and its Uses.--By JAMES PYKE.--Formation
      of carboniferous rocks and the coal in the same.--Processes of
      nature.--Greatness of this country due to coal.--Manufacture of
      gas.--Products of the same.

VIII. NATURAL HISTORY, BOTANY. ETC.--The Wine Fly.--The
      egg.--Larva.--Pupa and fly.

      The "Potetometer." an Instrument for Measuring the Transpiration
      of Water by Plants.--1 figure.

      Bolivian Cinchona Forests.

      Ferns.--Nephrolepis Davillioides Furcans and Nephrolepis Duffi.
      --2 engravings.

IX.   PHYSIOLOGY, HYGIENE, ETC.--The Upright Attitude of Mankind.
      --Review of a lecture by Dr. S.V. CLEVENGER, in which he
      tries to prove that man must have originated from a four footed
      being.

      Our Enemies, the Microbes.--Affections caused by the same.--
      Experiments of Davaine, Pasteur, and others.--How to prevent
      bacterides from entering the body.--5 figures.

X.    BIOGRAPHY.--Gaston Plante, the Scientist.--With portrait

      Warren Colburn, the American Mathematician.

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IMPROVEMENTS IN THE HARBOR OF ANTWERP.


The harbor of Antwerp, which, excepting those of London and Liverpool,
is the largest in Europe, has been improved wonderfully during the last
decade. Before 1870 it was inferior to the harbor at Havre, but now it
far surpasses the same. The river Scheldt, which is about 1,500 ft.
wide, was badgered out up to the vertical walls of the basin, so that
the largest ships can land at the docks. The river was deepened by the
use of caissons, in the lower parts of which the workmen operated in
compressed air. The annexed cut shows that part of one of the caissons
which projects above the surface of the water. The depth of the river at
low tide is about 26 ft., and at high tide about 39 ft. Some of the old
sluices, channels, basins, etc., which were rendered useless by the
improvements made in the river Scheldt have been filled up, and
thereby the city has been enriched by several handsome and elegant
