CONTENTS. V 



Number 195. 



Page 



Art. XX. — Mineral Sulphides of Iron ; by E. T. Allen, 

 J. L. Crenshaw, and J. Johnston ; with Crystallo- 

 graphic Study, by E. S. Larsen . _ . „ 169 



XXI. — Some Relations between Gravity Anomalies and the 



Geologic Formations in the United States ; by W. Bowie 23 7 



XXII. — Association of Native Gold with Sillimanite ; by T. 



L. Watson _ _ 241 



XXIII. — Hecker's Remarks on Ocean Gravity Observations ; 



by L. A. Bauer . 245 



XXIV. — Relations of the Degree of Metamorphism to Geo- 

 logical Structure and to Acid Igneous Intrusion in the 

 Narragansett Basin, Rhode Island ; by F. H. Lahee 249 



XXV. — Ilmenite Rocks near St. Urbain, Quebec ; A New 



Occurrence of Rutile and Sapphirine ; by C. H. Warren 263 



Chemistry and Physics — Quantitative Determination of Manganese, Raikow 

 and Tischkow : A Pernitride of Carbon, G. Darzens, 278. — Portland 

 Cement, E. Janecke : Annual Report of the International Committee on 

 Atomic Weights for 1912. — Hydrates of Sodium Carbonate, Wegscheider : 

 Canadium : Intrinsic Brightness of the Starlit Sky, C. Fabry, 280. — Mag- 

 netische Spektren der /3-Strahlen des Radiums, 281. — Production of Char- 

 acteristic Rontgen Radiations, R. Whiddington, 282. — Weitere Messungen 

 iiber Wellenlangennormale im Eisenspektrum, Evershetm, 283. — The Sun's 

 Energv-Spectrum and Temperature, C. G. Abbot, 284. — College Physics, 

 J. 0. Reed and K. E. Guthe, 285. 



Geology and Mineralogy — Geology of the Lake Superior Region, C. R. Van 

 Hise and C. K. Leith, 286.— Elastic-Rebound Theory of Earthquakes, H. 

 F. Reid,287. — La Sismologie moderne, Comte de Montessus de Ballore : 

 Periodic Variations of Glaciers : Interpretation of Peneplains, E. C. 

 Andrews, 288.— Australia in its Physiographic and Economic Aspects, G. 

 Taylor: Canada, Department of Mines, 289.— The present distribution 

 and origin of " Coal Balls," M. C. Stopes and D. M. S. Watson, 290. — 

 Early Paleozoic Bryozoa of the Baltic Provinces, R. S. Bassler : Fossil 

 Fish remains of the Cretaceous of New Jersey, H. W. Fowler : Types of 

 Ore Deposits, H. F. Bain, 292. — Brief Notices of some Recently Described 

 Minerals, 293. 



Miscellaneous Scientific Intelligence — Fourth Report of tho Wellcome Tropi- 

 cal Research Laboratories, A. Balfour, 294. — Einfiihrung in die Mykol- 

 ogie, A. Kossowicz : Principles of Human Nutrition, W. H. Jordan, 295. 

 Ostwald's Klassiker der exacten Wissenschaften, 296. 



Obituary— G. J. Brush : J. Lister : C. G. Wheeler : J. B. E. Bornet, 296. 



