Febeuaey 7, 1896.] 



SCIENCE. 



183 



youth, especially while pursuing his college 

 course at Yale, he made a study of the 

 plants of the region as a diligent botanist. 

 This early study was a valuable preparation 

 for his life's work, and its results were ex- 

 hibited in the use which he made of plants 

 in characterizing geologic periods. 



In 1838 he sailed with the Wilkes expe- 

 dition to explore the Pacific. This great 

 voyage was over the mighty ocean to un- 

 known lands of many climes, and for four 

 years he was allured by strange sights, at- 

 tracted by diverse objects of nature and 

 thrust into the midst of a vast field of ob- 

 servation. 



Here as a naturalist he engaged in the 

 study of marine life, giving especial atten- 

 tion to the zoophytes and Crustacea, and 

 laying the foundations of the knowledge of 

 zoology which was afterward woven into 

 the philosophy of the planet. The coral 

 animals are animate builders of continental 

 rocks, but he went beyond the structures 

 which they built to study the builders 

 themselves, their habits and the conditions 

 under which they live. Out in those lonely 

 seas, with savages for assistants, he studied 

 the builders and their constructions, the 

 animals and the atolls, the coral groves and 

 the arboreal denizens, and returned with a 

 vast accumulation of materials. Years were 

 required for their elaboration. With pa- 

 tience this labor was performed, until at 

 last he gave us an account of zoophytes and 

 also an account of the Crustacea, which is 

 in itself a monument worthy of a great man. 



From his schoolboy days he pursued 

 mineralogy as a field observer and by 

 mathematical investigation. Early he com- 

 menced to publish on this subject, weaving 

 the knowledge of his time into a systematic 

 body, reenforcing his own observations by 

 the observations of all others. Thus he 

 was the first to give us a system of mineral- 

 ogy ; but his work in this field did not end 

 at that stage. He still pursued his investi- 



gations, collecting from many fields and 

 drafting from the collections of others in 

 many lands, until at last he developed a 

 new system of mineralogy, placing the 

 science upon an enduring basis. This ac- 

 complishment alone was also worthy of a 

 great man, and by it a new science was or- 

 ganized on a mathematical, chemical and 

 physical basis. 



Here we see exhibited the integrity of 

 Dana's scientific character. In his first 

 work on chemistry he adopted a system of 

 nomenclature that involved a classification 

 which then seemed to be in harmony with 

 the practices of science, for he adopted a 

 system analogous to that used in zoology 

 which he advocated with acuteness, but 

 further investigation revealed to him that 

 his reasoning was wrong, that there was 

 a more natural and scientific method, 

 and he rent the whole fabric of his first 

 work into shreds and rebuilt a new and 

 better system. All honor to the man who 

 can thus sacrifice his consistency to the 

 truth. 



While Dana was in the midst of his scien- 

 tific work, Darwin announced the results of 

 his investigations into the origin of living 

 forms ; it was a great stroke of genius. The 

 doctrine which had been suggested and ably 

 advocated by Lamarck was established by 

 an inductive research in wide realms of 

 botany and zoology, and new laws of evolu- 

 tion were discovered. But Dana had al- 

 ready propounded a doctrine of serial 

 cephalization for animals, although not 

 fully seizing the principles of evolution ; 

 still it was a long step in that direction, and 

 he adjusted his philosophy to the new doc- 

 trine, and no great revolution was required . 

 This was generously and thoroughly done. 



We have seen Dana as a botanist, a 

 zoologist and a mineralogist. We are 

 next to see him in the great work of his 

 life, as a geologist. In 1833 he left Yale 

 College, before graduation, to become an 



