38 REPORT OF THE SECRETARY. 



liberality with wliicli lie was aided, the general appreciation of the 

 objects of the Institution, and the courtesy everywhere extended to him 

 personally. 



It was mentioned in the last report that a commencement had been 

 made, in connection with the Coast Survey, in the preparation of a 

 hypsometrical map of the United States, and that the elevation of 

 upwards of 9,000 points had been collected. This work has been 

 continued during the past year, and efforts have been made to obtain 

 materials existing in the offices of various railroads and public works, 

 and it has been deemed desirable still further to prosecute the research 

 among the archives at the State capitols. About 4,000 additional 

 elevations have thus been obtained, and considerable progress made 

 in the plotting of the material on the sheets of the hypsometrical 

 map. 



In furtherance of the same object, a small appropriation in addition 

 to the previous loan of instruments has been made to Prof. Guyot, to 

 assist in a hypsometrical survey of the Apalachian chain of mountains. 

 During the last two or three years, this accomplished geographer has 

 spent a considerable portion of the summer in North Carolina, and 

 has now nearly ready for publication a map of the part of the Apala- 

 chian system in that region. He has extended a net work of triangles 

 over an area of nearly 150 miles in length, and determined within 

 these, by a series of contemporaneous barometric observations, the 

 heights of all the more important peaks. 



In the report of his labors to the Institution, Professor Guyot makes 

 the following remarks : "I only deplore the absence of points the posi- 

 tion of which is determined astronomically or otherwise with sufficient 

 accuracy to enable me to locate my survey on the right spot of the surface 

 of the globe. The existing maps are very deficient in every respect." 

 In connection with this subject, I may be permitted to express the hope 

 that Congress will in due time make provision for extending the system 

 of triangulation which has been established with so much labor and 

 precision along the sea-board to the interior of the continent. The 

 necessity of such a work must every year become more and more evi- 

 dent, as the value of land increases and the precise definition of polit- 

 ical boundaries becomes more important. 



Ethnology. — Whatever relates to the nature of man is interesting to 

 the students of every branch of knowledge ; and hence ethnology affords 

 a common ground on which the cultivators of physical science, of 

 natural history, of archteology, of language, of history and literature, 



