CONTEXTS, 



Page 



Akt. I. — Researches in Acoustics; by A. M. Mayer 1 



II. — Petroleum in its relations to Asphaltic Pavement; by 



S. F. Peck?am 28 



III. — The age of tbe extra-moraine fringe in Eastern Pennsyl- 

 vania ; by E. H. Williams, Je 34 



IV. — Notes on the Cambrian Rocks of Pennsylvania, from 



the Susquehanna to the Delaware; by C. D. Walcott.. 37 



V.— The Internal Work of the Wind; by S. P. Laxgley. 



(With Plates I-V) 41 



VI. — Post-Glacial Eolian Action in Southern New England ; 



by J. B. Woodwoeth 63 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Production of Silver hyponitrite from Hydroxylamine, 

 W. Wislicenus: Electrolysis of Alkali Salts, Arrhenius, 72.— Preparation of 

 Chromium, Manganese and Uranium in the Electric Purnace, Moissan and Yiolle, 

 73. — Production of Sarcolactic acid by the Fermentation of Inactive Lactic acid, 

 Franklaxd and MacGregor: Heats of Combustion of Gaseous Hydrocarbons, 

 Berthelot and Matignon, 74. — Action of a Lsevolactic Ferment on Dextrose, 

 Ehamnose and Mannitol, Tate: Lead Tetracetate, Hutchinson and Pollard, 75. 

 — Thermochemistry of Chloracetic acid, Tanatat : A method of using the arc 

 light for reading rooms and libraries, Dobson: Application of light waves to 

 metrology, Michelson, 76. — Radiation of heated gases, Paschen: Electric 

 radiations in Copper Filings, Craft: Absorption of Electrical waves, Klem- 

 rncic: A new form of Contact maker, Bedell, Miller and Wagner, 77. 



Geology and Mineralogy — Geological Survey of Georgia, J. W. Spencer: The 

 Geology of Mexico, 78. — Geological Survey of New Jersey: Elementary Paleon- 

 tology for geological students, H. Woods: Geology of Boston Basin, Crosby, 79. 



Miscellaneous Scientific Intelligence — The Wilder quarter-century Book, 80. 

 Obituary — Dionts Stcr: John Ttndall, 80. 



