Janxjaby 15, 1897.] 



SCIENCE. 



89 



various points and interpreted them as 

 formed by water. No striation, polishing 

 or glacial topography were seen. All 

 seemed due to great accumulations in a 

 westward arm of the Mediterranean that 

 set in from Tunis and ran far up into the 

 mountainous country to the westward. 



The Relation of an Abandoned River Channel 

 in Eastern Iowa to the Western Edge of the 

 Illinois Icelobe. Fbank Levebett, Den- 

 mark, Iowa. 



The extension of the Illinois icelobe into 

 southeastern Iowa, discussed by the writer 

 at the Philadelphia meeting, is found to 

 have so blocked the drainage along the Mis- 

 sissippi that the line of discharge was tem- 

 porarily thrown across the plains of east- 

 ern Iowa. The several rivers of eastern 

 Iowa that now lead southeastward into the 

 Mississippi entered this temporary line of 

 drainage and followed it southward. A 

 description of the channel formed by this 

 temporary river was given, and the history 

 of the discovery of its several sections was 

 outlined. Inferences were drawn from it 

 concerning the drainage conditions at the 

 time of the culmination of the Illinois ice- 

 lobe. The paper was illustrated by a sketch 

 map of Iowa. 



F. B. Taylor asked about the channel 

 used by the river during its short cut into 

 its present channel between Cedar river and 

 Iowa river. Mr. Leverett replied that it 

 followed the present channel of the Iowa 

 river. Other remarks regarding the ancient 

 gradients of the river were made by Prof. 

 Eeid. 



Glacial Observations in the Umanak District, 

 Greenland. George H. Barton, Boston, 

 Mass. 



The result of studies upon the margin of the 

 inland ice for a distance of about fifteen miles 

 fi'om the nearest land was given. And the 

 character of the surface, of the marginal edges 



of very steep or vertical slope, of the dust holes 

 area, of the billowy area, and of the smooth, 

 level expanse beyond were described. Ice- 

 walled lakes, with small tributary streams, 

 and large streams were met. Studies upon 

 the Great Karajak glacier, its rate of mo- 

 tion, character of surface and margin, 

 movement phenomena as seen along edge, 

 entrance into waters of fi.ord, its source in 

 the ice cap with crevasses for miles inland, 

 proved of the greatest interest. Smaller 

 glacial tongues along the Karajak fiord, 

 coming from the local ice cap of the ISTug- 

 suak peninsula, were described, together 

 with studies upon the glaciers entering 

 Itivdliarsuk fiord and observations on the 

 former greater extension of the ice cap and 

 the distribution of drift and the transpor- 

 tation of material by icebergs. The paper 

 was graphicallj'^ illustrated by a beautiful 

 and significant series of lantern slides. C. 

 H. Hitchcock asked about marine deposits, 

 such as Champlain clays. Mr. Barton re- 

 plied that none were met. As Mr. Barton 

 had stated that the survey of the party had 

 indicated a slight movement of the ice up 

 stream near the shore, and down stream at 

 the outer stakes in the glacier, in each case 

 of but a fraction of a foot. Prof. Reid in- 

 quired about the accuracy of the instru- 

 ments, and cited the need of readings closer 

 than a minute. Mr. Barton replied that 

 they had been made with a high-grade sur- 

 veying transit, but as that part of the work 

 was directed by a colleague he could not 

 give further particulars. A. Heilprin stated 

 the occurrence of marine deposits with 

 shells in northwest Greenland. Mr. Bar- 

 ton's paper was one of the most interesting 

 and important of the meeting and coincided 

 with the observations of Prof. Tarr further 

 north as earlier cited. The British Admi- 

 ralty charts, for not using which Prof Wright 

 has been criticised, were found quite unre- 

 liable by Mr. Barton and were rejected in 

 favor of Danish maps. 



