IV CONTENTS. 



Number 182. 



Page 



Art. X. — Adjustment for the Plane Grating Similar to 



Rowland's Method for the Concave Grating ; by C. 



Barus and M. Barus _ . 85 



XI. — Determination of the Hardness of Minerals, II: by 



H.Z.Kip I... I... 96 



XII.— Photographing Fossils by Reflected Light ; by L. D. 



Burling 99 



XIII. — Synthesis of the Paleogeography of North America ; 



by E. Stjess ' 10 1 



XIV. — Estimation of Silver by Electro-Deposition from an 

 Ammoniacal Solution of the Oxalate ; by F. A. Gooch 

 and J. P. Feiser . . 109 



XV. — Notes on the Armored Dinosauria ; by G. R. Wieland 112 



XVI. — Original Gneissoid Structure in the Cortlandt Series ; 



by G. S. Rogers 125 



XVII. — Thaumasite from Beaver County, Utah; by B. S. 

 Butler and W. T. Schaller 1 131 



XVIII.— Nomenclature of the Lower Paleozoic Rocks of 



New York ; by H. P. Cushing 135 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Determination of Copper as Sulphate, Eecoura : 

 New Method for Determining Boiling Points and Vapor Pressures, Smith 

 and Menztes, 146. —Reactions of Nascent Hydrogen in the Dry Condition, 

 Vournassos : Synthetic Sapphire, Verneuil, 147. — Influence of Tem- 

 perature on the Compressibility of Metals, E. Gruneisen : Ionization of 

 the Atmosphere due to Radio-active Matter, A. S. Eve : Thomson Effect, 

 P. Cermak : Velocity Measurement of Rontgen Rays, E. Marx, 148. 



Geology— Osteology of Pteranodon, G- F. Eaton, 148. — The Age of Mam- 

 mals, H. F. Osborn, 150. — Tertiary Faunal Horizons in the Wind River 

 Basin, Wyoming, with Descriptions of New Eocene Mammals, W. 

 Granger, 151. — Geological Survey of New Jersey, Annual Report of the 

 State Geologist, H. B. Kumjiel, 152. 



Astronomy — Transactions of the Astronomical Observatory of Yale Uni- 

 versity, 152. — Determination of the Solar Parallax from photographs of 

 Eros, 153. — Les Determinations des Longitudes et l'Histoire des Chro- 

 nometres, J. Mascart : Project for the Reform of the Calendar, C. A. 

 Hesse, 154. 



Miscellaneous Scientific Intelligence — Report of the Secretary of the Smith- 

 sonian Institution, 155. — Report of the Librarian of Congress and Report 

 of the Superintendent of the Library Buildings and Grounds : Academic 

 and Industrial Efficiency, M. L. Cooke, 156. 



