he results and necessary formulae. 9793

New Method of Maintaining the Vibration of a
Pendulum.--Ingenious magneto-electric method of maintaining
the swinging of a pendulum. 9794

The Part that Electricity Plays in Crystallization.--C.
Decharme's investigations into this much debated
question.--The results of his work described.--3
illustrations. 9793

V. ENGINEERING.--A New Type of Railway Car.--A car with
lateral passageways, adapted for use in Africa--2
illustrations. 9792

Centrifugal Pumps at Mare Island Navy Yard, California.--By
H.R. CORNELIUS.--The great pumps for the Mare Island dry
docks.--Their capacity and practical working. 9792

Foundations of the Central Viaduct of Cleveland,
O.--Details of the foundations of this viaduct, probably
the largest of its kind ever constructed. 9792

VI. METALLURGY.--Chapin Wrought Iron.--By W.H. SEARLES.--An
interesting account of the combined pneumatic and
mechanical treatment of pig iron, giving as product a true
wrought iron. 9785

VII. METEOROLOGY.--On the Cause of Iridescence in
Clouds.--By G. JOHNSTONE STONEY.--An interesting theory of
the production of prismatic colors in clouds, referring it
to interference of light. 9798

The Height of Summer Clouds.--A compendious statement,
giving the most reliable estimation of the elevations of
different forms of clouds. 9797

VIII. MISCELLANEOUS.--The British Association.--Portraits
of the president and section presidents of the late
Manchester meeting of the British Association for the
Advancement of Science, with report of the address of the
president, Sir Henry E. Roscoe.--9 illustrations. 9783

IX. PHYSIOLOGY.--Hypnotism in France.--A valuable review of
the present status of this subject, now so much studied in
Paris. 9795

The Duodenum a Siphon Trap.--By MAYO COLLIER, M.S., etc.--A
curious observation in anatomy.--The only trap found in the
intestinal canal.