SCIENCE 



Editorial Committee: S. Nkwcomb, Mathematics; R. S. Woodwaed, Mechanics; E. C. Pickering 



Astronomy; T. C. Mendenhall, Physics; R. H. Thurston, Engineering; Ira Remsen, Chemistry; 



J. Le Conte, Geology; W. M. Davis, Physiography; W. K. Brooks, C. Hart Mereiam, Zoology; 



S. H. SCUDDEE, Entomology; C. E. Bessey, N. L. Britton, Botany; Henry F. Osboen, 



General Biology; C. S. Minot, Embryology, Histology; H. P. Bowditch, Physiology; 



J. S. Billings, Hygiene ; J. McKeen Cattell, Psychology; Daniel G. Bein- 



TON, J. W. Powell, Anthropology. 



Friday, March 31, 1899. 



CONTENTS: 



A National Observatory 465 



Discussion of a National Observatory : Professors 

 Simon Newuomb, Asaph Hall, C. A. Young, 

 T. C. Mendenhall, R. S. Woodward, C. L. 

 Doolittle, W. H. Pickering, Arthur 

 Searle, Frank W. Very, David P. Todd, 

 G. W. Myees, E. a. Fueetes, W. L. Elkin, 

 James E. Keelee 467 



T/ie Atomic Weights — A Quarter Century's Prog- 

 ress : Professor F. P. Venable 477 



Hermaphroditism in Ostrea Lurida : PROFESSOR 

 F. L.Washburn 478 



Agrirultural Eleciroiechnics : PROFESSOR R. H. 

 Thurston 480 



Scientific Books : — 



Geology of the Edwards Plateau and Bio Grande 

 Plain: Peofessoe Feedeeic W. Simonds. 

 Sully' s Medical Climatology : De. G. HiNSDALE. 481 



Scientific Journals and Articles 485 



Societies and Academies : — 



Biological Society of Washington : O. F. CooK. 

 The Washington Botanical Club : Dr. Charles 

 Louis Pollard. The iVeio York Section of the 

 A^nerican Chemical Society : Dr. DuRAND 

 Woodman. Section of Astronomy and Physics 

 of the Neio York Academy of Sciences : R. Gor- 

 don. Academy of Scieiice of St. Louis : Pro- 

 fessor William Teelease 486 



Discussion and Correspondence : — 



Plymouth, England, and its Marine Biological 

 Laboratory : Dr. Edwaed G. Gardiner. The 

 Duplication of Geologic Formation Names : F. B. 

 Weeks. The Berlin Tuberculosis Conference : 

 De. Ch. Waedell Stiles 488 



Astronomical Notes : — 



The Buiherfurd Photographs ; The Solar Eclipse 



of May SS, 1900 : PROFESSOR WiNSLOW UPTON 492 



Notes on Physics : — 



The Effect of Commutators on the Field of Dyna- 

 mos and Motors; Telegraphy and Magnetic Jn- 

 duction:F.C. C 493 



Tlie Bequests of the late Professor Marsh 494 



Scientific Notes and News 494 



University and Educational Nmos 496 



MSS. intended for publication and books, etc., intended 

 tor review should be sent to the responsible editor, Profes- 

 sor J. McKeen Cattell, Garrison-on-Hudson N. Y. 



A NATIONAL OBSERVATORY. 



The letters wMcli we publish in this 

 number from prominent American astrono- 

 mers on the general subject of a national 

 observatory may be regarded as a sequel to 

 Professor Skinner's admirable history of 

 the Naval Observatory found in our issue of 

 January 6tli. Justice to the latter institution 

 demands that we should point out certain 

 features of the case which have generally 

 been overlooked. It has been too hastily 

 assumed that the Naval Observatory should 

 fill the requirements of a national astro- 

 nomical observatory, and that, if it did not, 

 some one must be at fault. To correct this 

 view we have only to cite some authorita- 

 tive statements on the subject. The matter 

 was stated very forcibly and clearty by 

 Commodore Belknap, Superintendent of the 

 Observatory, as far back as 1885, when 

 the building of the new observatory was 

 about to begin, and when, in consequence, 

 its purposes were the subjects of public dis- 

 cussion. He wrote : 



It is first of all a naval institution, its astronomical 

 work being, so far as the naval service proper is con- 

 cerned of a purely secondary consideration. * ■^' ^ * 

 If the time has come when the purel}' scientifio side 

 of the institution has outgrown the needs of the naval 

 service the converse is true, namely, that the navy 



