VOL. LVl] ESTAB LISHEB BT EPWAHD L. YOOHAM. [NO. 5. 



APPLETONS' ^ 



POPULAR SCIENCE 



MONTHLY. 



EDITED Br WILLIAM JAT TOUMAXS. ^'^ 



MARCH, 1900. 



J^^-^jh- 



TXM* 



The Transplantation of a Eace. Prof. n. S. Sealer. 513 



Modem Cit J Roadways. (Illustrated.) Nelson P. Lewis, C. E. 524 



Typical Criminals. (Illustrated.) Rev. Samuel G. Smith, LL. D. 539 



A Century of Geology. (Concluded.) Prof. Joseph Le Conte. 546 



"Salamanders" and "Salamander" Cats. aHustrated.) Prof. Noeman Robinson. 556 



What makes the Trolley Car go. (Ulus.) (Concluded.) William Baxter, Jr., C. E. 564 



A SurylTal of Mediaeval Credulity. Prof. E. P. Evans. 577 



"Ribbon Lightning." aHustrated.) Orange Cook. 587 



Cross-Education. (Illustrated.) Prof. E. W. Scripture. 589 



The Morbid " Sense of Injury." W. P. Becker, M.D. 596 



Early Experiments in Air Flight. M. Banet Rivet. 603 



Sketch of Edward Orton. (With Portrait.) 607 



Editor's Table : A Commission in Difficulties.— The Function of the Public Library. . . 614 



Fragments of Science 528 



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