AMERICAN GEOLOGY — KATnNIAN ERA. 1820—1829. 



259 



Harden was the first to suggest the name Ternary for formations 

 of alluvial origin and more recent than the secondary. The secondary 

 formations he regarded as " the results of a natural operation;" that 

 is, as natural deposits from water, probably in a state of perfect tran- 

 quility. The alluvial, on the other hand, were the results of "acci- 

 de n tal operations . * ' 



These essays were very favorably reviewed by Silliman in the third 

 volume (1821) of his journal, even the idea of the fusion of the polar ice 

 cap being allowed to pass with no more serious criticism than to suggest 

 that the flood of waters might have been produced through the expul- 

 sion of the same from cavities in the earth. J. E. De Kay. writing in 

 1828. ventured, however, to. take exception to some of the expressed 

 views regarding drift bowlders. He wisely suggested that since the 

 speculative part of geology is but a series of hypotheses we should in 

 every ease admit that which explains the phenomena in the simplest 

 possible manner. To his mind the simplest manner of explaining the 

 presence of bowlders of primitive rocks scattered over a secondary or 

 alluvial region was to suppose that such had been, as. igneous materials, 

 extruded through all superincumbent strata, forming peaks which 

 have since been destroyed by some convulsion of nature or by the 

 resistless tooth of time, the bowlders thus 

 being but fragments which had escaped 

 destruction, though their place of extrusion 

 had become completely obscured. 



Hayden's career was varied and interest- 

 ing. Earh T thrown on his own resources, 

 with an ardent desire for knowledge and 

 craving for travel, he went to sea at the age 

 of fourteen, making two voyages to the West 

 Indies, after which he re- 

 sketch of Hayden. turned to his school and his 

 books. When sixteen years 

 of age he was bound out to an apprenticeship 

 with an architect, with whom he served until 

 he reached his majority, when he once more sailed for the West 

 Indies and established himself at Point a Pitre in Guadeloupe Island, 

 one of the Lesser Antilles. Ill health, however, finally drove him 

 back to America, where he found employment in his profession in 

 Connecticut and New York, with occasional intervals of teaching, in 

 which, it was stated, he was very successful. 



Through accident his attention was turned to dentistry, and with no 

 preliminary training and only such knowledge as could be gained by 

 reading, he established himself in the practice of that profession in 

 Baltimore, somewhere about 182-1, being then, it will be observed, 

 between fifty and sixty years of age. In this work he is represented as 



Fig. 12.— Horace H. Havik-n. 



