Scientific Serials

Abstract

American Journal of Science, November.—Geology of Southern Patagonia, by J. B. Hatcher. This is an account of the results of an expedition into Argentine Patagonia made for the purpose of collecting vertebrate fossils for Princeton University. The oldest sedimentary deposits seen were a series of black, very hard, but much fractured slates, with Ammonites fairly abundant, but not sufficiently well-preserved to admit of identification. These beds are referred to the Jurassic, chiefly on account of their lithological characters and the great thickness of the overlying rocks, which, to judge from Dinosaurian remains, can hardly be more recent than the Cretaceous. The beds of basalt observed by Darwin on ascending the Santa Cruz River are not due to a flow from the distant Cordilleras, but to small local craters.—The former extension of the Appalachians across Mississippi, Louisiana, and Texas, by J. C. Branner. Gives additional facts in support of his thesis that the old Appalachian land area crossed what is now the lower Mississippi valley. The coal-measures drainage of the Illinois-Indiana-Kentucky basin flowed westward through the Arkansas valley into a carboniferous Mediterranean sea. The drainage of the coal-measures region south of the Ouachita anticline flowed westward and entered this sea north of the Texas pre-Cambrian area. The drainage of both the Arkansas and Texas carboniferous areas was reversed about the end of Jurassic times, when orographic movements over south-east Arkansas, eastern Texas, Louisiana, and Mississippi submerged the former extension of the Appalachian watershed, and admitted the early Cretaceous sea across the Palaeozoic land as far north as southern Illinois.—The combustion of organic substances in the wet way, by I. K. Phelps. Carbon dioxide may be estimated iodometrically with a fair degree of accuracy. It may, therefore, be applied to the determination of organic carbon oxidised fry liquid reagents, such as potassium permanganate or chromic acid. The former was used for oxidising oxalates, formates, and tartar emetic; the latter for these and cane-sugar and paper. The method is very successful in the case of the less volatile organic compounds.—Some features of the pre-glacial drainage in Michigan. In all the glaciated area of North America no region is so extensively and deeply covered with drift as the lower peninsula of Michigan. The author works out the probable features by analogy with unglaciated areas, and constructs a map showing the probable carboniferous river system.