November 7, 1890.] 



SCIENCE. 



265 



'Nonsense!' at the mere question. Both the top and bottom of 

 the wheel must of necessity, it would seem, be moving forward at 

 one and the same rate; i.e., the speed at which the carriage is 

 travelhng. Not so, however, as a little reflection would convince 

 you. The top is moving in the direction of the wheel's motion of 

 translation, while the bottom is moving in opposition to this mo- 

 tion: in other words, the top is moving forward in the same 

 directipn in which the carriage is progressing, while the bottom is 

 moving backward or in an opposite direction. That is why an 

 instantaneous photograph of a carriage in motion shows the upper 

 part of the wheel a confused blur, while the spokes in the lower 

 part are distinctly visible." 



— Messrs. Houghton, Mifflin, & Co. have just published as a 

 second reader, "Fables and Folk Stories," phrased by Horace E. 

 Scudder. This book contains literature which the world has cho- 

 sen to remember. Mr. Scudder's literary taste, clearness of style, 

 and heart}' sympathy with children, have enabled him to clothe 

 these classic stories in classic language suitable for children who 

 are prepared for a second reader. The first half of the ''Fables 

 and Folk Stories " has also been published as No. 47 of the River- 

 side Literature Series The second half will be published on Dec. 

 3 as No. 48 of the same series. 



— Messrs. Kegan Paul, Trench, Triibner, & Co.'s October an- 

 nouncements include among many others the following of special 

 interest to our readers:" " Essays, Scientific and Philosophical," by 

 the late Rev. Aubrey Lackington Moore; "The Philosophy of 

 Right," by Professor Diodato Lioy, translated from the Italian by 

 W. Hastie, B.D.; "Confucius, the Great Teacher: a Study," by 

 Major-Gen. G. G. Alexander, C.B.; "The Life of Philip Henry 

 Gosse, F.R.S.," by his son, Edmund Gosse; "Disraeli and his 

 Day," by Sir William Eraser; "Turanian Stock: being a New 

 Division of 'Social History of the Jlaces of Mankind,' " by A. 

 Featherman; " Free Exchange: Papers on Political and Economi- 



cal Subjects," with an unpublished treatise on the law of value, 

 and the unearned increment theory, by the late Right Hon. Sir 

 Louis Mallet, C.B., edited by Bernard Mallet; "Socialism New 

 and Old," by William Graham, professor of political economy and 

 jurisprudence, Queen's College, Belfast; "On the Modification of 

 Organisms," by David Syme; "General Physiology: a Physiologi- 

 cal Theory of Cosmos," a rectification of the analytical concept of 

 matter, and of the synthetical concept of bodies, resolving the 

 problem of the unity of all objective knovvledge, by Camilo Cal- 

 leja, M.D. ; " Theory of Physics: a Rectification of the Theories of 

 Molar Mechanics, Heat, Chemistry, Sound, Light, and Electricity," 

 by Camilo Calleja, M.D. ; "Air Analysis: a Practical Treatise on 

 the Examination of Air, with an Appendix on Illuminating-Gas," 

 by J. Alfred Wanklyn and W. J. Cooper; "Soups and Stews and 

 Choice Ragouts: Practical Cookery Recipes," prepared by Miss T. 

 Cameron, diplome National Training School of Cookery: "Afghan 

 Poetry of the Seventeenth Century ; being Selections from the Poems 

 of Khush Hal Khan Khatak," with translations and grammatical 

 introduction by C. E. Biddulph, M. A. ; " Kahun, Gurob. and 

 Hawara," by W. M. Flinders Petrie. with chapters by F. LI. 

 Griffith and Percy E. Newberry; "Arabic Chrestomathy," in 

 Hebrew characters, with a glossary edited by Hartwig Hirsch- 

 feld, Ph.D. ; " Bihari Proverbs," by John Christian. 



— Messrs. E. & F. N. Spon announce that they have nearly 

 ready a second edition, considerably enlarged, of Maycock's 

 " Electrical Notes and Definitions," for the use of engineering 

 students and pr.-^ctical men, with the rules and regulations to be 

 observed in electrical installation wcrk, as issued by the Phoenix 

 Fire Office and the Institution of Electrical Engineers (with numer- 

 ous illustrations, 33mo, roan, price $1.75). 



— Messrs. William M. & J. C. Goldthwaite, New York, announce 

 a new geographical magazine, embracing every thing in the geo- 

 graphical news line. Cyrus C. Adams of the New ¥©rk Sun is 



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