888 PROCEEDINGS OF THE ACADEMY OF [DeC, 



amount of some ten to fifteen tons, and the question as to wliether or 

 not the hypothetical main body of the meteorite formed the crater in 

 question in its impact with the eartli has been the subject of numerous 

 speculations and papers, notably by Professor Gilbert, of the United 

 States Geological Survey, and others. The shape and general appear- 

 ance of the crater, together with the absolute and entire absence of all 

 evidence of volcanic action in or around it, manifestly inclined these 

 early observers to decide this question, at least tentatively, in the 

 affirmative, and they regarded the matter as worthy of further investi- 

 gation. In pursuance of this object Professor Gilbert devised what 

 he at the time, regarded as two crucial experiments to determine the 

 presence or absence of a large amount of meteoric iron in the bottom of 

 the crater. These were, first, a topographical survey of the hole and 

 rim by which he made their contents approximately ec^ual, and there- 

 fore gave no room for the presence of the bulk of the very considerable 

 body required to produce such a hole by its impact; and secondly, a 

 magnetic survey of the locality, which by its negative results was thought 

 to preclude the possibility of the presence of any considerable mass of 

 metallic iron in the vicinity. By these two experiments the question 

 seemed to be authoritatively decided in the negative and the whole 

 matter has remained in abeyance for many years. 



The author of this present paper, having had his attention called to 

 the matter by his friend Mr. D. M. Barringer, has examined the locality 

 with great care, and with ]Mr. Barringer has done a considerable amount 

 of development work there, and as a result of the facts disclosed there- 

 by is very strongly of the opinion that the hole and its rim were pro- 

 duced in exactly the way at first supposed by the earlier investigators, 

 and wishes here to bring to notice several points in support of the cor- 

 rectness of this theory which have escaped notice, or at least mention, 

 in the papers of the earlier investigators of this most interesting 

 locality. 



It is first, however, necessary to criticise the so-called crucial experi- 

 ments of Professor Gilbert, upon the results of which he definitely aban- 

 doned the theory of the meteoric formation of the crater in cjuestion, 

 as, if these can be regarded as definite^ settling the matter in the nega- 

 tive, there is no use in bringing forward facts looking towards its prob- 

 ability, no matter how plausible they may be. In regard to the first 

 of these crucial experiments, that is, the alleged identical contents of 

 the rim and the hole. In reply to this it can only be said that the 

 author has also made surveys of this locality, and is very sure that the 

 contents of the rim not only does not show the excess over that of the 



