CONTENTS. 



Page 



Art. X. — Mechanical Equivalent of the Heat Vaporization - 



of Water; by R. H. Hough _._:\^ 81 



XI. — Phosphorescence of Zinc Sulphide through the Influence 



of Condensed Gases obtained by Heating Rarb-Earth 



Minerals ; by C. Baskkrville and L. B. Loci^hart 93 



XII. — Action of Radium Emanations on Mineralp^and Gems; 



by C. B askerville and L. B. Lockhart ...... 95 



XIII. — Behavior of Typical Hydrous Bromides when Heated 



in an Atmosphere of Hydrogen Bromide ; by J. L. 



Krkider 97 



XIV. — Glacial (Dwyka) Conglomerate of South Africa ; by 



E. T. Mellor _. ., 107 



XV. — Formation of Natural Bridges ; by H. F. Cleland.. 119 

 XVI. — Quartz from San Diego County, California ; by G. 



A. Waring ._ . 125 



XVII. — Radio-active Properties of the Waters of the Springs 



on the Hot Springs Reservation, Hot Springs, Ark.; bv 



B. B. Boltwood. 1 128 



XVIIL— Genesis of Riebeckite Rocks; by G. M. Murgoci . 133 

 XIX. — Purpurite, anew Mineral; by L. C. GRATON.and W. 



T. Schaller ._/ 146 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Studies with the Liquid Hydrogen and Air Calori- 

 meters. I. Specific Heats, J. Dewar, 152. — Thermo-electric Junction as 

 a Means of determining the Lowest Temperatures, J. Dewar, 153. 



Geology — Geology of the Vicinity of Little Falls, Herkimer County, H. P. 

 Cushing, 156. — Geology of the Watkins and Elmira Quadrangles, accom- 

 panied by a geologic map, J. M. Clarke andD. D. Luther, 157. — Geologic 

 map of the Tully Quadrangle, J. M. Clarke and D. D. Luther, 158. — 

 Contribution to the Paleontology of the Martinez Group, C. E. Weaver : 

 Faune cambrienne du Haut-Alemtejo (Portugal), J. F. N. Delgado, 159. 

 — Paraphorhynchus, a new genus of Kinderhook Brachiopoda, S. Weller : 

 Sympterura Minveri, n. g. et sp. ; a Devonian Ophiurid from Cornwall, F. 

 A. Bather : Ancestral origin of the North American Unionidae, or fresh- 

 water Mussels, C. A. White, 160. — Thalattosauria, a group of marine rep- 

 tiles from the Triassic of California, J. C. Merriam : Geology of Littleton, 

 New Hampshire, C. H. Hitchcock : Vorschule der Geologie, J. Walther, 

 161. — Die Moore der Schweiz mit Berucksichtigung der gesammten Moor- 

 frage, J. Fruh and C. Schroter, 162. — Study of Recent Earthquakes, C. 

 Davison : Introduction to the Geology of Cape Colony, A. W. Rogers, 

 163.— Ice Erosion Theory, a Fallacy, H. L. Fairchild, 164. — Hanging Val- 

 leys, I. C. Russell, 165. — Glaciationof the Green Mountains, C. H. Hitch- 

 cock : Ice or Water, H. H. Howorth, 166. 



Miscellaneous Scientific Intelligence — United States National Museum, R. 

 Rathbun : Forestry ; Tenth Annual Report of the Chief Fire Warden of 

 Minnesota, C. C. Andrews : Les Prix Nobel en 1902 : Negritos of Zam- 

 bales, W. A. Reed : Magnetic Survey of Japan reduced to the Epoch 

 1895*0 and the Sea-level, A. TAnakadate, 167. — Beitrage zur chemischeh 

 Physiologie, F. Hofmeister : Du Laboratoire a 1' Usine, L. Houllevigue : 

 Traite Complet de la Fabrication des Bieres, G. Moreau and L. Levy, 168. 



