LIFE OF JAMES DWIGHT DANA 



he had no time to waste on those who studied geology 

 only as a matter of form, his resources were freely at the 

 disposal of any who displayed intelligent interest in the 

 subject. 



" One way in which he evinced this was by the long 

 walks which he was wont to take with his students about 

 New Haven, or other trips to places more distant. 

 Though these were over the same ground year after year, 

 he never seemed to weary of the journey so long as his 

 students showed any desire to be instructed by what they 

 saw. Even to the very last of his life these trips were 

 continued, the teacher of nearly fourscore years travelling 

 over rocky steeps and through brambly thickets with all 

 the ease and sprightliness of youth and at a pace which 

 his younger followers found difficult to imitate. The 

 number and variety of illustrations of geological prin- 

 ciples which he could point out in such walks of a few 

 hours were indeed remarkable, and taught his students 

 that they need not go to distant parts of the earth to 

 make geological observations, for they could find material 

 sufficient for study at their own door. The trap-ridges, 

 kettle-holes, and boulder trains of the vicinity of New 

 Haven have thus become of classic interest, not because 

 they presented any unusual features, but because Profes- 

 sor Dana resided near them, studied them, and gave to 

 the world the results of his observations. 



" No operation that was carried on within the range of 

 his observation, the details of which could add to the sum 

 of geological knowledge or help solve any of its problems, 

 seemed to escape his notice. Every railroad cut, every 

 survey, every excavation, and every boring he carefully 

 watched, and gained from them facts which helped him 

 interpret the past history of the earth. 



" The bricks which were burned in the Quinnipiac kilns 

 he had analyzed in order to learn why they fused so 

 easily, and gained thereby important information regard- 

 ing the source of the clay. By the dolomitic blocks of 

 the State-house he illustrated to his classes the principles 

 of the disintegration of limestone, and by the granite 

 pillars of the Peabody Museum the expansion of stone 

 by heat. From watching the drying of a drop of milk on 

 a stone floor he derived an explanation of the forms pro- 

 duced by concretionary consolidation, and by experi- 



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