Gum Arabic and its Modern Substitutes.--A continuation of a
paper by Dr. S. Rideal and W.E. Youle.--With 26 tables
A New Method of Extinguishing Fires.--Invented by George
Dickson and David A. Jones, of Toronto, Canada.--Apparatus designed
to utilize a mixture of water and liquefied carbonic acid
VI. Medicine and Hygiene.--The Hygienic Treatment of
Obesity.--By Dr. Paul Chebon.--Methods of eating, drinking,
and exercising for the purpose of reducing fat.--An extended
article, giving valuable information to people troubled with too
much flesh
VII. Photography.--Spectroscopic Determination of the Sensitiveness
of Dry Plates.--A full description of the new plan of
Mr. G.F. WILLIAMS, for determining the sensitiveness of dry
plates by the use of a small direct vision pocket spectroscope
VIII. Physics.--A Physical Laboratory Indicator.--By J.W.
MOORE, of Lafayette College.--1 engraving.--This is a modification
of the old peg board adapted to use in the laboratory.--It indicates
the names of the members of the class, contains a full
list of the experiments to be performed, refers the student
to the book and page where information in reference to experiments
or apparatus may be found, it shows what experiments
are to be performed by each student at a given time, etc.
Cailletet's Cryogen.--A description, with one engraving, of Mr.
Cailletet's new apparatus for producing temperatures from 70
degrees to 80 degrees C., below zero, through the expansion of
liquid carbonic acid
IX. Technology.--The Manufacture of Roll Tar Paper.--An extended
article containing a historical sketch and full information
as to the materials used and the methods of manufacture
Smokeless Gunpowder.--By Hudson Maxim.--A comprehensive
article on the manufacture and use of smokeless gunpowder,
giving a sketch of its history, and describing the methods of
manufacture and its characteristics
Method of Producing Alcohol.--A description of an improved
process for making alcohol.--Invented by Mr. Alfred Springer,
of Cincinnati, Ohio
* * * * *
[Illustration: INTERIOR OF THE NEW LABOR EXCHANGE, PARIS.]
[Illustration: NEW LABOR EXCHANGE, PARIS.]