Scientific American Supplement, No. 623

ຢScientific American Supplement

The Project Gutenberg EBook of Scientific American Supplement, No. 623,
December 10, 1887, by Various This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.net
Title: Scientific American Supplement, No. 623, December 10, 1887
Author: Various
Release Date: July 12, 2005 [EBook #16270]
Language: English
Character set encoding: ISO-8859-1
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SCIENTIFIC AMERICAN SUPPLEMENT NO. 623

NEW YORK, DECEMBER 10, 1887
Scientific American Supplement. Vol. XXIV., No. 623.
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. ARCHITECTURE.--Notes on the Construction of a Distillery Chimney--A new method of building lofty shafts, including a metallic frame and brick lining--3 illustrations. 9949
The Commercial Exchange, Paris--The new Paris exchange now in process of erection.--Present state of operations--1 illustration. 9954
II. ASTRONOMY.--The Yale College Measurement of the Pleiades.-- Dr. Elkin's work with the Repsold heliometer at Yale College. 9957
III. CHEMISTRY--New Method for the Quantitative Determination of Starch.--By A.N. ASBOTH--Determination of starch by its barium compound. 9956
Synthesis of the Alkaloids--A retrospect of the field of work so far traveled over by synthetical chemists, and future prospects. 9956
The Chemical Basis of Plant Forms--By HELEN C. DE S. ABBOTT --Continuation of this important contribution to plant chemistry, one of the most valuable of recent chemical monographs. 9955
IV. ELECTRICITY.--An Electrical Governor--A new apparatus for preserving a constant electromotive force with varying dynamo speed--1 illustration. 9952
Electric Launch--A French government launch with Krebs electric motor. 9954
The electric current as a means of increasing the tractive adhesion of railway motors and other rolling contacts.--By ELIAS E. RIES--A full review of this important subject, with accounts of its experimental examination. 9953
V. ENGINEERING--Benier's Hot Air Engine--A new caloric engine very fully illustrated and described--8 illustrations. 9943
Heating Marine Boilers with Liquid Fuel--A simple apparatus and recent experiments with the same.--3 illustrations. 9945
The Change of Gauge of Southern Railroads in 1886--By C.H. HUDSON.--The conclusion of the account of this great engineering feat, with tables of statistics and data--16 illustrations. 9946
Your Future Problems--By CHAS. E. EMERY--An address to the graduating class of the Stevens Institute, N.J.--A practical view of the engineering profession. 9943
VI. MISCELLANEOUS--A Group of Hampshire Downs--A typical breed of sheep, their qualities and habits.--1 illustration. 9957
VII. NAVAL ENGINEERING--The Spanish Cruiser Reina Regente--A further description of this celebrated vessel--4 illustrations. 9948
Torpedo Boats for Spain--The Azor and Halcon, two Yarrow torpedo boats, described and illustrated--7 illustrations. 9947
VIII. PHOTOGRAPHY--How Different Tones in Gelatino-chloride Prints may be Varied by Developers.--Twenty different formul? for the above purpose. 9949
Film Negatives--Eastman stripping films, their manipulation and development. 9949
IX. SANITATION--French Disinfecting Apparatus--A portable apparatus for disinfecting clothes and similar objects--1 illustration. 9952
X. TECHNOLOGY.--The Manufacture of Cocaine--The extraction of cocaine with alkali and petroleum, with statement of percentage yielded by various leaves. 9954
The Production of Oxygen by Brin's Process--The commercial manufacture of oxygen by means of baryta--3 illustrations. 9950
#Transcriber's Note: Following entry not in original table of contents#
Deep Sea Dredgings: Examination Of Sea Bottoms. By THOMAS 9958 T.P. BRUCE WARREN.
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BENIER'S HOT AIR ENGINE.
The hot air engine, although theoretically recognized for some time past as the most economical means of converting heat into motive power, has up to the present met with little success. This is due to the fact that the arrangement of the motors of this class that have hitherto been constructed has been such as to render them but slightly practical. In the Benier hot air engine (illustrated herewith), however, obstacles that were once considered insurmountable have been overcome, and the motor presents many advantages over all the types that have preceded it. Among such advantages we shall cite the possibility of utilizing air at a high temperature (1,200 or 1,500 degrees), while the rubbing surfaces remain at a moderate temperature (60 or 80 degrees). The fire grate is placed in the interior of the cylinder, and is traversed by the cold air forced by a pump. The expanded hot gases fill the cylinder and act against the piston directly above the grate.
The type herewith illustrated is of 6 horse power. The motive cylinder, CC', is bolted to the extremity of the frame, A. Upon this latter is fixed a column, B, which carries a working beam, E. This latter transmits the motion of the piston, P, to the shaft, D. A pump, G, placed within the frame, forces a certain quantity of cold air at every revolution into the driving cylinder. The piston of this pump is actuated by the connecting rod, G', jointed to the lever, F', which receives its motion from the rod, F. A slide valve, _b'_, actuated