3O PHYSICAL GEOGRAPHY. 



limited resources, much reliance was placed upon estimates of the loca- 

 tion of the contour lines, without actual measurement. Hence this model 

 is only an approximation to a correct representation, but is sufficiently 

 accurate to enable all interested in the study of the mountains to compre- 

 hend the relative altitudes and courses of the ranges, especially as they 

 stand related to the distribution of the formations. 



After the exhibition of this model in public, information was furnished 

 that a model of the White Mountains had been fashioned in plaster, sev- 

 eral years since, by Rev. Dr. Thomas Hill, lately president of Harvard 

 college. This was upon a much smaller scale, about eighteen inches 

 square, and was built up upon the basis of Bond's Map of the White 

 Mountains, published in 1853. It includes the Franconia region, and all 

 the mountains as far south as Waterville and Conway. An inspection 

 of this representation shows great familiarity with the structure of the 

 mountains, and it is a matter of regret that its existence has been known 

 to so few persons. A copy of it has been presented to us by the author, 

 and is placed in the state museum at Hanover. 



So numerous were the localities requiring visitation, that six of the 

 members of the class of 1871 of Dartmouth college, C. S. D., were in- 

 vited to assist in the work of exploration. These were B. W. Andrews, 

 W. B. Douglass, C. J. Johnson, J. F. Pratt, E. Thompson, and Frank 

 Woodbridge. Aid was also furnished by J. H. Huntington, Dr. Nathan 

 Barrows, and E. Hitchcock, Jr. We procured the necessary provisions 

 and other supplies, and lived among the mountains, in extempore camps, 

 till the various points had been explored and the required observations 

 made. Without so many assistants, the early completion of the model 

 would have been impossible ; and all who take pleasure in contemplating 

 the results are under obligations to these gentlemen for their very 

 arduous labors. 



That it is very difficult to climb high mountains is a statement which 

 no one will deny. Most persons who visit our New Hampshire mountains 

 are well satisfied with their labors when a single peak has been ascended 

 on foot. They are willing to accept almost any theory that may be pro- 

 posed to explain their geological structure, because immense labor would 

 be required to disprove it. The task before us was the dissipation of 

 all false notions, and the discovery of the real stratigraphical structure 



