CONTENTS 



Page 



Aet. LI. — Effect upon the earth's velocity produced by small 



bodies passing near the earth ; by H. A. Newton 409 



LIT. — Trend and Crnstal Surplusage in Mountain Structures; 



by A.. Winchelx .. 417 



LILT. — The Genealogy and the Age of the Species in the 



Southern Old-tertiary ; by O. Meyer 421 



LIV. — The Condensing Hygrometer and the Psychrometer ; 



by H. A. Hazen ". 435 



LV. — A new form of Absorption Cell ; by A. E. Bostwick.. 452 

 LVI. — Fossils in the Hudson River Slates of the southern 



part of Orange County, N. Y., and elsewhere; by N. H. 



Dabton 452 



LVIL — Report of the American Committee-delegates to the 



Berlin International Geological Congress; by P. Feazer, 454 

 LVIII. — Bright Lines in Stellar Spectra ; by O. T. Sherman, 475 

 LIX. — Optical Properties of Rock-salt; by S. P. Langlet.. 477 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics. — Reaction of Barium sulphate on Sodium carbonate, under 

 pressure, Spring : Sulphocyanuric acid, Hofmann, 481. — Synthesis of Cocaine, 

 Merck: Hydrogen Persulphide, Sabatier, 482. — Valence of Phosphorus, Mi- 

 chaelis and La Coste, 483. — Measurement of the Resistance of Liquids, Bouty 

 and Foussereau, 484. — Method of measuring the vibratory periods of tuning- 

 forks, A. M. Mater, 485. 



Geology and Natural History. — Report of the U. S. Geological Survey, J. W. Pow- 

 ell, 486. — Precious Metal deposits of the "Western United States, S. F. Emmons 

 and G. F. Becker : Malesia, Plantse Ospitatrici: Illustrationes Flora? Atlanticte, 

 481. — Physiological Botany, G. L. Goodale: Rabenhorst's Kryptogamen-Flora 

 von Deutschland, Oesterreich und der Schweiz, von K. G. Limpricht : Structure 

 and Dehiscence of Anthers, Leclerc du Sablon, 488. — Influence of strong sun- 

 light on the vitality of Micrococcus, M. Duclatjx : Histology of Ascidia, Heckel 

 and J. Charetre : Reserve Carbohydrates in Fungi, L. Errara, 489. 



Miscellaneous Scientific Intelligence. — Elements of Projective Geometry, L. Cremona 

 and C. Leudesdorp, 489.— National Academy of Sciences, 490. — Obituary — Dr. 

 "W. B. Carpenter, 490. 



Index to Volume XXX, 491. 



TEN-VOLUME INDEX. 



An extra number of this Journal, containing an index to volumes xxi to xxx, 

 of sixty pages or more, will be ready in January. The publication of this num- 

 ber involves a large extra expense to the editors, and it will be sent, therefore, 

 to those only who specially order it. The price is seventy-five cents per copy. 

 Orders are solicited, as the edition will be a small one. 



^fc***£++ 



