382 



SCIENCE 



[N.S. V0E.XXVIIL No. 716 



of " ballons-sondes," that there was a warm, or 

 isothermal, stratum in the atmosphere at a height 

 of about 10 kilometers. In 1904 the author made 

 the first use of " ballons-sondes " in the United 

 States and in this and the following years sent 

 up 77 balloons from St. Louis. Nearly all of the 

 71 recovered which rose higher than 12 kilo- 

 meters entered the warm stratum. The largest 

 inversion of temperature found was during the 

 first ascension on September 15, 1904, when the 

 minimum temperature of — 52° C. occurred at 

 a height of 14,600 meters, the temperature rising 

 to — 36° C. at 17,000 meters, the maximum 

 height attained. Again, on October 8, 1907, the 

 temperature fell to — 67° C. at 14,500 meters 

 and rose to — 58° C. at 16,500 meters, the 

 stratum of inversion descending 2,500 meters 

 within the next two days. In summer its level 

 is somewhat lower than at other seasons. It 

 seems probable that this warm stratimi extends 

 completely around the globe. It lies lower in 

 northern Europe, but it was not discovered at 

 the equator by the balloons that rose 15 kilo- 

 meters from a yacht sent to the South Atlantic 

 in 1906 by M. T. de Bort and the author. 

 Discussed by Professor T. C. Chamberlin. 



High-level Terraces of New England: J. W. 



Spences. 



The author presented and described longitudinal 

 sections of the river valleys radiating from the 

 White Mountains. They show a succession of 

 terrace steps descending the valleys, the surfaces 

 of which slope very gently down the valleys, each 

 one passing by abrupt transition to the next 

 below. Each begins in a river flat, becoming a 

 terrace further down the stream, where remains 

 01 several terraces, one above the other, may be 

 seen. In one case, as in the Lemaile Valley, the 

 slope was found to be forty-five feet in fifteen 

 miles. These phenomena are found from the high 

 mountain passes, such as Profile and Crawford 

 notches, to within a few hundred feet above sea 

 level. They suggest that in them be found data 

 bearing on the Post-glacial elevation of the moun- 

 tain masses. 



Discussed by Professor J. W. Goldthwaite. 



Note upon the Structure of the Pre-Camhriwn, 

 Oneiss of the Santa Catalina Mountains, Ari- 

 zona: Wm. p. Blake. 



The Pre-Cambrian gneiss of the Santa Catalina 

 Mountains is remarkable for its tabular stratifi- 

 cation at a low angle of dip; its permeation by 

 pegmatite with the formation of feldspar nodules. 



and its extreme foliation in some parts, passing 

 from coarse-grained gneiss to schists in various 

 forms, micaceous and hornblendic. 



But the chief characteristic to be here noted 

 is its evident elongation under great pressure. 



Studies of the Tracks of Climatichnites : C. H. 



Hitchcock and W. Patten. 



A large slab of sandstone crossed by several 

 trails was exhibited where installed on the walls 

 of Butterfield Museum. Professor Patten de- 

 scribed the movements of a modern Limulus in 

 advancing up a sandy beach with the tide and 

 the action of the abdominal gill plates making 

 rhythmic ridges in the sand. He compared these 

 with the tracks of Climatichnites, which he as- 

 cribed to forms related to the Eurypterids rather 

 than the trilobites. The tracks showed a begin- 

 ning in a hollow in the sand and where continued 

 on the specimen to the further end there became 

 fainter, as if the animal rose from the bottom. 

 This would correspond with the habit of the 

 Limulus, which remains buried on recession of 

 the tide and upon its return first crawls and then 

 swims away. Beside one track were seen two 

 symmetrically placed impressions attributed to 

 the longer arms of a Eurypteroid form. 



The Attitude of the Algonquin Beach; and its 



Significance: J. W. Goldthwaite. (Illustrated 



by lantern slides.) 



Precise measurements of altitude of the Algon- 

 quin beach and other " raised beaches " bordering 

 Lake Michigan indicate that in that basin the 

 Algonquin beach slants southward at a repeatedly 

 diminishing rate, becoming horizontal near Man- 

 istee, Mich., and Kewaunee, Wis. South of a line 

 through these localities the Algonquin beach is 

 invariably 593-598 feet A. T. This horizontality 

 over the southern half of the Lake Michigan 

 basin appears to mean that the beach there is 

 now at the altitude at which it stood when first 

 formed, and that it has been undisturbea by those 

 differential uplifts which have warped the more 

 northerly parts of the Great Lake district. In 

 other words, Lake Algonquin appears to have 

 stood approximately 600 feet A. T. when the 

 " Algonquin Beach " was built. 



Mr. F. B. Taylor found what is probably the 

 same beach at an altitude of 1,220 feet A. T. near 

 South River, 30 miles south of the pass between 

 Lake Nipissing and the Mattawa River. It is 

 quite possible that the plane of this Algonquin 

 beach, extended over the Nipissing Pass, would be 

 at least 1,300 feet A. T. there. If so, that dis- 



