4a 



1ntkrkstin(; Decosit ok Ai-umina Oxyhyuratk. IJy (iko. W. Hknton. 



[Ahstract.] 



1. Report of trip to Southwest Missouri, March, 1894. 



2. Alumina found in pool of spring water. 



3. The springs brought in the deposit. 



4. A careful survey of tlic region proved that tlic dejiosit is forming, ami is. 

 Mot stored up in (juantity. 



5. TIic source a i)uro aluminum silicate wliich abounds in quantity in that 

 region. 



0. Some possible uses of the deposit and the silicate. 

 7. Theory of the decomposition. 



Observations on the Glacial Driit of Jasi>er County, by A. H. Pibdue. 



The writer begs to state tliat his experience in glacial geology, the time 

 spent in field work on the material herein presented and the territory explored 

 are all limited ; and that he does not claim for the paper any more than its title 

 indicates, viz.: observations on the glacial drift of the locality named. It is 

 proper to state further that these ob.servations have been confined mainly to that 

 part of the county lying soutli of the Iroquois River. 



Jasper County is situated in the northwestern part of the State, with Porter 

 County intervening between it and Lake Michigan, and is separated from the 

 State of Illinois by Newton County. It is, therefore, in one of the most active fields 

 of all the glacial epochs. Mr. Collett claims (Twelfth An. Rejjort Geol. and 

 Nat. Hist, of Ind., page 66, ) that glacial erosion has removed from fifty to two 

 hundred feet of rock from the entire surface of tlie county. This great erosion, 

 and subsequent glacial action, has left it practically level, and with poor drain- 

 age, so that numerous peat marshes abound in all parts of the county, varying in 

 size from a half acre and less to several thousand acres. Notably among the 

 larger ones are "GifiTord Marsh," a swamp of 12,000 or 15,000 acres, lying twelve 

 miles northeast of Rensselaer, and the "Blue Sea," a similar marsh, lying in the 

 southeastern part of the county. Only the former of these has been visited by 

 the writer. It is an old glacial lake filled up with peat and muck, varying in 

 depth from three to fifteen feet, the monotony of which is broken by numerous 

 »cc-umulations of sand, which in form imitate drumlins. 



Many wells have been drilled in all parts of the county, but no compilation 

 of the data furnished by them has been made, so that nothing is known of the sub- 

 glacial topography. It might be stated, however, that the drift varies in depth 



