886 PROCEEDINGS OF THE ACADEMY OF [DeC, 



judging by the results of artillery experiments, we have termed the 

 inner or interior crater, somewhere in which we suppose the wreck of 

 the meteoric body to lie. In all of the holes the material (silica, 

 broken and whole sand grains and some pieces of dense layers of ce- 

 mented material composed largely of carbonate of lime) brought up by 

 the drill from underneath the lacustrine sedimentary formations shows 

 when concentrated many minute fragments of iron shale or minute shale 

 balls which contain an appreciable percentage of nickel, and are therefore 

 doubtless meteoric in nature. It seems certain that much of the nickel 

 has been leached from these fine particles of meteoric material, but not- 

 withstanding this fact they invariably have been found to contain a small 

 fraction of one per cent, of this element, and in other respects are gen- 

 erally similar to the fine particles of iron shale which we have found on 

 the outside of the crater. This evidence, to say the least, is strongly 

 corroborative of, if not absolute proof of, the above theory. To test it 

 still further, however, we are now proceeding to sink with a steam 

 hoist a double compartment shaft in the exact center of the crater. 

 Unless we should be prevented by difficulties which we cannot over- 

 come, this will be sunk to such depths as will demonstrate the existence, 

 as we suppose in a fragmentary condition and several hundred feet 

 below the central plain, or the non-existence of the extra-terrestrial 

 body which, in my best judgment, produced when it collided with the 

 earth the crater which I have endeavored to describe.^" 



^"It should be borne in mind that this paper treats only of such facts as. are of 

 interest to the scientific world, and has no reference whatever to the commercial 

 value of the discovery. 



