686 ABSTRACTS OF PAPERS 



meteor-impact origin of the remarkable depression a few miles to the eastward 

 known as Coon Butte or Meteor Crater. On the recent visit to the locality 

 during the transcontinental excursion of the American Geographical S<: 

 opportunity was afforded to inspect closely the occurrence of many of the 

 dized irons" found in the debris around the margin of the crater. Of sixteen 

 samples collected of the unaltered kernels of the-r masses all proved to be 

 simply ordinary hematite and not metallic iron, as claimed. 



The instructive feature to be noted in this connection is that throughout the 

 arid regions the small isolated iron-ore masses formed at or near the surface 

 of the ground are not usually the hydrous iron oxide or limonite. as is the case 

 in regions of moist climate, but the anhydrous minerals hematite and magtT 

 Only under exceptional conditions when brought into contact \mh damp clays 

 do the iron minerals change into the limonite variety. 



There are still important finds of true meteoric iron in the neighborhood of 

 Coon Butte, but the greater part of the materials passing - such are hematitic 

 in character and not of celestial origin. 



JfEW OCCURRENCE OF MONAZITE IX NORTH CAROLI: 

 BY JOSEPH HTDE PRATT 



(Abstract) 



This paper describes an occurrence of monazite where the mineral is in a 

 tals and jme of which weigh 60 pounds. Some of the crystals are 



well developed and are as much as 2 3 4 inches long. These crystals and masses 

 of monazite are the largest the author hr sen. 



NEW 0CCURR7 )MS LARGI 7^7?.0LITES FROM 



DUCKTOWX. EE 



BY FBA2VK B. VAX HORX 



Absi i 



In an open cut at Isabella, near Ducktown. Tennessee, considerable amounts 

 of a green and blue de: i-ondarv origin were observed by the author in 



the summer of 1912. This was at first thought to be melanterite and chalcan- 

 thite. but a few tests and analyses have shown that the two substances are 

 pisanite. with a varying percentage of iron and copper. The staurolite crystals 

 are the largest ever seen by the writer. They are evidently entirely altered to 

 mica and contain many inclusions of gamr 



SPECULATIVE XA7 



BY W. M. DAVIS 



(Abstrc 



The opinion prevails in many places that geology is chiefly an observational 

 science. This is not correct- It is chiefly a speculative science, in that the 

 great body of its statements go far beyond the field of observable fact into the 

 field that can be reached only by means of speculative mental processes. The 

 recognition of this truth carries with it two important consequence that 



