EDWARD HITCHCOCK. 



297 



to the Hudson River group, their associates, as represented by 

 Sir William E. Logan, insisted that the quartzite in western 

 Vermont overlaid the slates, and was of Medina age. Logan 

 also claimed a synclinal structure for the Green Mountains. 

 Before accepting any conclusion as to their structure, Prof. 

 Hitchcock directed that this mountain range should be carefully 

 studied stratigraphically. A dozen sections were made at equal 

 distances apart across the State, and it was discovered that the 

 structure was anticlinal when not monoclinal ; and hence comes 

 the certainty that the axis of the Green Mountain chain is older 

 than lower Cambrian. The latest workers in this field accept 

 this conclusion. 



Perhaps the favourite subject of Prof. Hitchcock was the 

 study of the " Drift." He began to study the icemarks, even 

 before the discovery of the footprints, and soon found himself 

 far beyond the comprehension of his literary and scientific 

 associates. Neither the iceberg nor glacier theory was original 

 with him ; but no one up to the time of his death had pub- 

 lished so much upon the subject. His views are developed in 

 the treatise on Surface Geology published by the Smithso- 

 nian Institution in 1857. His general theory refers the phe- 

 nomena to both icebergs and glaciers ; and their setting forth 

 was generically like the most recent deliverances of Sir William 

 Dawson, who acknowledges the presence of glaciers upon the 

 mountains from which the icebergs were derived that flooded 

 the submerged valleys. His papers are of special interest con- 

 cerning river terraces, local glaciers in western New England, 

 trains of boulders, and frozen deposits of drift gravel. It is 

 an interesting fact that he argued against the admissibility of 

 Agassiz's glacial theory because of the absence of a grand ter- 

 minal moraine at the outer margin of the ice sheet. It was 

 less than five years after his death that geologists began to 

 appreciate the true significance of the backbone of Long Island 

 that it was part of a gigantic moraine more than a thousand 

 miles long. It is easy to see where Hitchcock would have 

 stood had these facts been known in his day. 



The first written suggestion in regard to the formation of 

 the American Association of Geologists came from Prof. Hitch- 

 cock, and he was chosen its first president in 1840. This was 

 the parent of the later organization known as the American 

 Association for the Advancement of Science. He was present 

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