Produced by Juliet Sutherland, Huub Bakker, and the Online Distributed Proofreading Team at www.pgdp.net [Illustration] SCIENTIFIC AMERICAN SUPPLEMENT NO. 664 NEW YORK, SEPTEMBER 22, 1888 Scientific American Supplement. Vol. XXVI., No. 664. Scientific American established 1845 Scientific American Supplement, $5 a year. Scientific American and Supplement, $7 a year. * * * * * TABLE OF CONTENTS. PAGE I. ARCHITECTURE.--The Commercial Exchange, Paris.--History of the new building, with its general design and architectural features.--2 illustrations 10607 The New Central Railway Station at Frankfort-on-the-Main.--A full description of this gigantic structure, with its constructive features and cost.--2 illustrations 10605 II. ART OF WAR.--Gun Practice in the French Navy.--Gun practice at sea against a moving target.--1 illustration 10599 Modern Cavalry on the Field of Battle.--By Col. R. S. LIDDELL.--An exhaustive paper on this subject, treating of a much discussed branch of military tactics 10600 III. BIOLOGY.--Subterraneous Flora and Fauna.--By Dr. Otto Zacharias.--A popular article on the interesting subject of animal and vegetable life underground.--8 illustrations 10612 IV. CHEMISTRY.--Pepsin.--By A. PERCY SMITH, F.I.C., F.C.S.--The analysis of pepsin, difficulties of the usual method, and simple comparative test, applicable by any one 10611 V. CIVIL ENGINEERING.--Timber and Some of Its Diseases.--By H. MARSHALL WARD.--Continuation of this valuable series, treating of fungus life and its destructive effects.--5 illustrations 10613 VI. ELECTRICITY.--A Basis from which to Calculate Charges for Electric Motor Service.--A practical paper treating of the percentage of horse power hours used in different industries 10608 VII. ETHNOLOGY.--A Chinese Imperial Cemetery.--The cemetery of the emperors of the Ming dynasty.--The remarkable statues and buildings.--2 illustrations 10610 How a Mound was Built.--An interesting contribution to the history of the Ohio mounds by Mr. GERARD FOWKE 10609 Some Abyssinian Customs.--The hair dressing of the Abyssinian women.--Their method of grinding pepper.--3 illustrations 10609 VIII. MEDICINE AND SURGERY.--A New Surgical Operation.--Dr. Brudenell Carter's operation for relieving pressure on the optic nerve 10611