568 



THE POPULAR SCIENCE MONTHLY, 



Indnstrial Educational Association, New Tork. 

 Reports, 1SS8. Pp. 24. 



Ingersoll, Col. R. G. The Stage and the Pulpit. 

 New York: The Truth-Seeker Company. Pp. \i. 



Judge Publishing Company. Napoleon Smith. 

 Pp. 202. 50 cents. 



Judge's Young Folks' Monthly. New York : 

 Judge Publishing Company. Pp. 2-1. 15 cents. 

 $1.50 a year. 



Longshore, T. E. Our Lord and Saviour Jesus 

 Christ. Truth-Seeker Company. Pp. 13. 



Manager, Peder. Pictures of Hellas. Trans- 

 lated by Mary J. Saflford. New York: Wm. S. 

 (iottsberger. Pp. 318. 



Morris, Charles. The Aryan Race. Chicago: 

 8. 0. Griggs & Co. Pp. 847. $1.50. 



Miiller, Max. The Science of Thought. Chicago : 

 Open-Court Publishing Co. Pp. 28. 75 cents. 



Nebraska, University of. Catalogue and Regis- 

 ter, 18H7-'Sa Pp. 112. 



Oswald. Felix L. The Bible of Nature. New 

 York : The Truth-Seeker Company. Pp.240. $1. 



Pennsylvania College of Dental Surgery, Phila- 

 delphia. Twenty-third Annual Announcement. 

 Pp. 16. 



Philosophical Society of Washington. Bulletin. 

 Vols. IX, X. Smithsonian Edition. Vol. X. So- 

 ciety's Edition. 



Pickering, Edward C. Second Annual Report 

 on Photographic Study of Stellar Spectra. Pp. 8 

 with 2 Plates. 



Quick, M. W., Titusville, Pa. Modem Specula- 

 tion. Pp. 84. 



Ripley, Chauncey, University of New York, 

 Law Department. Address on Presentation of Me- 

 morial Portrait of John N. Pomeroy, etc. Pp. 25. 



Starr, Dr. Elmer, Buifalo, N. Y. Photographing 

 the Interior of the Living Human Eye. Pp. 5. 



Stockham, G. H., M. D., Oakland, CaL Temper- 

 ance and Prohibition. Pp. 131. $1. 



Todd, J. E. Directive Coloration in Animals. 

 Pp.7. 



University of lUinms. Agricultural Experiment- 

 al Station. Bulletin No. 1. May, 18S8. Pp. 13. 



Washburn, L. K. Religious Problems. New 

 York : The Truth-Seeker Company. Pp. 23. 



WolflF, Alfred R. Efficiency of Mechanical Engi- 

 neering Schools. Pp. 7. 



Wright. G. Frederick. The Age of the Ohio 

 Gravel Beds. Pp. 9. 



Wright, Rev. T. F. The Realities of Heaven. 

 Philadelphia : William H. Alden. Pp. 120. 



Woman's Medical College of Pennsylvania. 

 Thirty-ninth Annual Announcement. Pp. 24. 



Woman's Medical College of the New York In- 

 firmary. Twentieth Annual Catalogue and An- 

 nouncement. Pp. 20. 



POPULAR MISCELLANY. 



The Dynagraph.— From a description of 

 this instrument, which its inventor, Mr. P. 

 H. Dudley, read before the New York Acad- 

 emy of Sciences, we select a few notes. The 

 first dynagraph was made in 1874, and used 

 paper eleven inches wide for its records. A 

 later instrument uses paper of twenty or 

 thirty inches width as desired. The record- 

 ing apparatus occupies a floor space of about 

 thirty-four by forty inches, in a car specially 

 constructed for its use, and is thirty-seven 



inches high. It is placed over a special six- 

 wheel truck, which carries many distinct sets 

 of apparatus to furnish required indications, 

 the results being electrically recorded by the 

 battery of electro-magnetic pens on the re- 

 cording apparatus. As the car moves, the 

 paper is fed through the instrument, the rate 

 when inspecting track being one inch of 

 paper for each fifty feet of track. The ap- 

 paratus may, if desired, take the dynamo- 

 metrical curve, and inspect the track at the 

 same time. From this curve, the number of 

 foot-pounds of work expended in moving the 

 train any selected distance is calculated. All 

 movements of the cut-off, up or down, or of 

 the throttle-valve, in or out, are shown by 

 the curve. Aside from all other conditions, 

 each engineer, especially on a freight-train, 

 gives the curve a personal equation, a good 

 one, if he is a first-class runner, thoroughly 

 acquainted with the line, so he is able to 

 work his locomotive to the best advantage, 

 saving in fuel and time. Such engineers can 

 draw more cars, with a given locomotive, 

 than those who are not so well versed. One 

 practical result of the use of the dynagraph 

 was the discovery which has been verified in 

 practice, that for freight-trains, on the Lake 

 Shore and Michigan Southern Railroad, the 

 locomotive gave a much more economical 

 development of power running eighteen to 

 twenty miles an hour, than when running ten 

 to twelve miles. Further, the saving in run- 

 ning time of a train from Chicago to Buffalo 

 was twenty-four hours, giving the road a 

 much greater capacity with the same equip- 

 ment. The track inspection includes the 

 measurement of surface undulations and side 

 deflections in the rails, the measurement of 

 gradients, and of the curvature and alignment 

 of the line. Lines are also traced showing 

 the distance passed over, the time in seconds, 

 side oscillations of car, the consumption of 

 each cubic foot of water, and each twenty- 

 five or fifty pounds of fuel, the velocity of 

 wind, revolutions of drivers, intervals of 

 firing, and duration of black smoke. Any 

 special piece of electrical recording apparatus 

 can be put in circuit with a pen, and its indi- 

 cations recorded. From the character of the 

 delineations it is at once seen whether the 

 rails are rough and bent, joints low, worn 

 out, or loose on the ties, and whether any 

 permanent improvement which can be made 



