November 22, 1895.] 



SCIENCE. 



707 



older formations, Carbouiferous-Triassic ; in late 

 Tertiary or early Pleistocene times a forest 

 growth was apparently thrown down and soon 

 covered by coarse sediments, after which perco- 

 lating waters replaced the vegetable matter 

 with silica. The existence of the widespread 

 gravels necessitates belief in an equally wide- 

 spread plain in late Tertiary or Pleistocene 

 times. An uprising of perhaps a few hundred 

 feet gave opportunity for wearing away the 

 gravels and the upper part of the older forma- 

 tions, and the valley systems broadened and 

 interlocked to produce mesas and outliers, while 

 streams gained a meandering habit to some 

 extent. A second and great uplifting to the 

 present plateau altitude gave opportunity for 

 the greater drainage lines to cut deep trenches 

 with precipitous sides. The subordinate drainage 

 in the Carboniferous limestone region seems to 

 reach the canon bottoms chiefly by underground 

 channels, the old surface valleys showing small 

 traces of recent worlt, while on the other hand 

 the development of sinlv holes has begun. In 

 the sandstone and shale regions the water in 

 part goes underground to the main channels ; in 

 part it is carving the plateau surface by a system 

 of 'box canons.' 



The volcanic work would appear to have 

 begun after denudation of the Tertiary or Pleis- 

 tocene plain had progressed far, but before the 

 second or caiion elevation ; the large number 

 of volcanic masses in all stages of destruction 

 evinces a pretty continuous activity until perhaps 

 the last few centuries. 



THE ACADEMY OF SCIENCE OF ST. LOUIS, MO., 

 NOVEMBER 4, 1895. 



The Academy held its regular meeting with 

 President Green in the chair and thirty-three 

 members and visitors present. 



Prof. Francis E. Nipher, as a committee ap- 

 pointed liy President Green, read a memorial 

 of the late Prof C. V. Riley, dwelling briefly 

 upon Prof. Riley's life and work, and especi- 

 ally his great achievements in the field of 

 economic Entomology. 



Prof. H. S. Pritchett presented a communi- 

 cation on ' The Resume of Certain Studies of 

 the Satellite System of Saturn,' calling atten- 

 tion to the remarkable similarity between this 



system and the solar system, and also the fre- 

 quent eclipses to which the satellites of Saturn 

 are subjected. 



A very interesting exposition was given of 

 the effect of the attraction of the large satellite 

 Titan upon the smaller Hyperion, resulting in 

 great eccentricity of the orbit of Hyperion and 

 a rapid revolution of its pericentric. Mention 

 was also made of the curious phenomena of the 

 satellite I^etus being much brighter on one 

 side than on the other, and of its revolution on 

 its axis coinciding with its revolution around 

 the planet. 



The paper was followed by a discussion as to 

 the nature of the Saturnian system of rings and 

 satellites. 



Prof. Nipher presented a paper on ' The Law 

 of Minimum Deviation of Light by a Prism.' 



Adjourned. A. W. Douglas, 



Recording Secretary. 



SCIENTIFIC JOURNALS. 

 JOURNAL OF GEOLOGY, OCTOBER-NOVEMBER. 



On the Cliffs and Exotic Blocks of North Switzer- 

 land: By E. C. QuEREAU. Certain exotic 

 rock masses occurring along the north border 

 of the Alps and Carpathian mountains have 

 long been more or less a puzzle to geologists. 

 They occur on the Flysch, which is Eocene, 

 while the fossils found in the cliff's have been 

 pronounced by Professors Kaufmann, Stein- 

 mann and the author to be Jurassic. Two ex- 

 planations have been offered for the phenome- 

 non : First, that the cliffs were forced up 

 through the newer rocks. Second, that they 

 were thrust over them. Of these hypotheses 

 the author maintains the latter. He finds the 

 source to the north in a mountain system ' das 

 Vindelisische Gebirge," now buried under the 

 Miocene of the Swiss plain, the existence of 

 which was predicated on entirely different 

 grounds by Professor Studer and other Swiss 

 geologists. 



The Preglacial Valleys of the Mississippi and its 

 Tributaries: By Frank Leveeett. That 

 drainage systems were greatly changed by the 

 advance of the ice is no longer doubted. The 

 author has in this paper gathered a large 

 amount of data with reference to preglacial 



