CONTEXTS. 



Pa*e. 



Art. XXXVI. — The Electrical Resistance of Stressed Glass; 



by Carl Barus... ... 339 



XXXVII. — Formation of Siliceous Sinter by the Vegetation 



of Thermal Springs; by Walter Harvey Weed 351 



XXXVIII.— Marine Shells and Fragments of Shells in the 



Till near Boston ; by War run TJpham 359 



XXXIX.— A Platiniferous Nickel Ore from Canada ; by F. 



W. Clarke and Charles Catlett 372 



XL. — Stratigraphic Position of the Olenellus Fauna in North 



America and Europe; by Chas. D. Waloott 374 



XLI. — Earthquakes in California ; by Edward S. Holden. 392 

 XLII. — Chemical Action between Solids ; by Wm. Hallock 402 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics. — Spectrum of Magnesium, Liveing and Dewar: Lecture 

 Experiment for showing Raoult's Molecular depression of the Freezing Point, 

 Cimician. 406. — Chydrazaine or Protoxide of Ammonia, Maumene, 407. — New 

 Stannic Acid, Spring: Ethyl Fluoride, Moissan, 408. — Chemical Lecture Notes, 

 P. T. Austen: Elementary Text-Book of Chemistry, W. G Mixter : Rays of 

 Electric Force, Hertz: Rotation of plaue of polarization of light by the dis- 

 charge of a Leyden jar, 0. Lodge, 409. — Limit to Interference when Light is 

 radiated from moving Molecules, Ebert, Ratleigh: Selective Reflection by 

 Metals, Reubens, 410. 



Geology and Mineralogy. — Recent Discoveries in the Carboniferous Flora and 

 Fauna of Rhode Island, A. S. Packard: Annual Report of the Geological Sur- 

 vey of Arkansas for 1888, J. C. Branner, 411. — Cretaceous and Tertiary Geol- 

 ogy of the Sergipe-Alagdas basin of Brazil, J. C. Branner : Tertiary Volcanoes 

 of the Western Isles of Scotland, J. W. Judd, 412.— Numnmlites up the Indus 

 valley at a height of 19,000 feet, T. D. LaFouche: Sand-drift rock-sculpture, 

 R. D. Oldham: Catalogue of Fossil Cephalopoda in the British Museum, A. H. 

 Foord : Nature and Origin of Deposits of Phosphate of Lime, R. A. F. Pen- 

 rose, Jr., 413. — Fulgurites of Mt. Viso, F. Rutley: Scheelite from Idaho, W. 

 P. Blake: Hiilfstabellen zur mikroskopischen Mineralbestimmung in Gesteinen 

 zusammengestellt von H. Rosenbusch : Les Mineraux des Roches par Le>y 

 and Lacroix, 414. 



Botany. — Contributions to American Botany, XVI, Sereno Watson, 415. — Key 

 to the System of Victorian Plants, F. von Mueller, 416. — Revision of 

 North American Umbelliferae, J. M. Coulter and J. N. Rose : Flora Italiana, 

 Oaruel : Diagnoses plantarum novarum asiaticarum, C. J. Maximowicz : 

 Orchids of the Cape Peninsula, H. Bolus, 417. — Handbook of the Amaryllidese, 

 J. G. Baker : Synoptical List of North American Species of Ceauothus, W. 

 Trelease and C. C. Parry, 418. — Multiplication of Bryophyllum calycinum, 

 B. W. Barton: Enumeratio Plantarum Guatemalensium imprimis a H. 

 DeTuerckheim, J. D. Smith: Journal of Andre Michaux: Annals of Botany: 

 Herbarium of the late Rev. Dr. Joseph Blake: Outlines of Lessons in Botany, 

 J. H. Newell, 419. 



Miscellaneous Scientific Intelligence. — Deep-sea depression in the Pacific near Ton- 

 gatabu: Dredging Stations in North American Waters, S. Smith: National 

 Academy of Sciences, 420. — Proceedings of the U. S. National Museum : Exami- 

 nation of Water for sanitary and technical purposes, H. Lefpman and W. Beam, 

 421. 



Obituary. — Annie E. Law: Hetnrich von Dechen: Giuseppe Meneghini: 

 Theodor Kjerulf: John Ericsson, 422. 



