CONTENTS. ". 
NUMBER CXI. 
Pa 
Arr. XXII.—Chart of the Magnetic Declination in the United “3 
States, constructed by J. E. Hirearp. With Plate V,. 173 
XXII.—The Old River-beds of California; by J. LeConrn, 176 
XXI AG oe on the Age of the Green Mountains ; 3 by J. 
XXV. —Nev ‘Action of the “Magnet o on Electric Currents ; ‘by 
E. H. Hatt, - ODES SOE ISE sven 200 
XXVI. anol of the Polar and Equatorial ‘Diameters of 
; by OUN Sa IN a ee 206 
XXVII.—Use of the Sgt for the Diurnal Variation 
of Temperature ; ae : 212 
XXVIII. “The Chawies Composition of the Uraninite from 
Branchville, Conn. ; by W. J. Comsrocn, ..--.-.--.--- 220 
one Bis an Free Path of a Miasleede:: ; "by N. D. C. 
a oe ee 
XXX, — Western Limits of the Taconic System ; by” S. W. 
Fite SPO ap hs Si ai POT ouses loo ee 
XXXL. ~Pvitiaipal ‘Characters of American Jurassic 725 
saurs; by O. C. Marsn. With Plates VI to XI, -..... 253 
SCIENTIFIC INTELLIGENCE. 
Chemistry and Physics. Obie learatay! of bears) vaurOR MEYER: Action of 
Phosgene gas on om nia, FENTON, 226.— car uoran Pigoatcog Frrnie, 
227.—Introducti of yates xyl 1 direct Osidation, I 
Constitution oF Piorodicciviens: DEMOLE —Archil- febens a California, 
ESS ermination of Sulphur i i: cae ; re and 
tical Tre: the Manufacture of Sulphuric Acid and Alkali, G. Lunges, 
230.—The Chemistry of Common Life, W. JOHNSTON, 231.—“* Why 
—Report on Magnetic Determinations in Missouri in the Summer of 1879, F. 
Nipuer, 234.—-Variations in the Magnetic ar ete at Moncalieri (Piedmont): 
New Action sso Magnets on Electric Currents, KE. H: Hab, 235. 
Geology and Mineralogy.—Geology of the Rio Sao a. Brazil, 0. A. DERBY 
Age of the eagle rocks and Geology of Vermont, E. and ©. H. Hrrcxcock, 
Pipe Raat “a the Silurian Fossils of the Girvan District in Ayrshire, H. 
phase and R. ErHeripGs, Jr.: Spodumene and its Alterations, A. A. 
JULIEN, 2: 37.—Crystals of Wollastonite, O. Root, 239. 
Zoology.—Fresh-water Rhizopods of North America, J. Lerpy, 240.—Zoology ie 
Students and General Readers, A. S. PAacKARD, Jr., 244.—Das System der 
Medusen, E. Hacker, 245,—List of Daidging ne Stati tions, B. Pirroe and ©. P. 
Patrerson: Ophiuride and A rosin T. Lyman: Cotton Worm, ©. V. 
, 248. 
Astronomy.—C atalogue of the Eibrety of the U. S. Naval Observatory, E. 8. 
HOLDEN Sgr gect an ne “% Cincinnati Observatory: Catalogue of the mean 
declination of 2018 H, Sar FORD, ae Fa Bc of the Astrono: mical 
Observatory of Harvard G ites E. C. Picks 
Scientific Intelligence.—The i tabans Institution, W. J. RaEgs: 
Erasmus Phirwin, E. KRavse, 250.—Blowpipe Analysis, J. LANDAUER: Ameri- 
can Journal of Mathematics, J. J. Sy.vester: Narrative of the Polaris, 251.— 
Bernhard von Cotta Fund: The Naturalist’s ekeerty: New Geological Map 
of the United States: M. Dumas: Erratum, 252. 
