A PHYSICAL ATLAS OF NORTH AMERICA. 



A COMMUNICATION FROM GEO. GIBBS, ESQ. 



Washington, May 4, 1865. 



My Dear Sir : The collection by the Institution of materials for the form- 

 ation of a physical atlas of the United States was among the objects con- 

 templated by yourself in the original programme of its organization, and it appears 

 to me that the time has now arrived when its formation should be laid on a scale 

 commensurate in magnitude and variety of subject with the scientific progress of 

 America, embracing all the departments of natural, physical, and social science 

 capable of beiug represented in such a form, and extended in its design to the 

 entire continent, since the boundaries of the United States are accidental and 

 governed by none of the laws which control the operations of nature. 



The completion of such a work, and its ultimate publication in a collected 

 shape, would, of course, require years, and the expense might render assistance 

 from Congress necessary. This, however, is a matter for future consideration. 

 The arrangement of the materials already on hand, and what may hereafter be 

 collected, will require but a moderate outlay and should be entered upon at 

 once. It reflects but little credit on our national enterprise that almost the 

 only physical charts of Araei'ica should be of foreign origin. 



As a necessary preliminary it is essential that good skeleton maps be prepared, 

 and these should, in my opinion, embrace the following : 



1st. A series of maps of natural geographical regions, exhibiting the hydro- 

 graphy of the country with minuteness, but on which only the principal moun- 

 tain systems should be given, and those in curves without hachures. These 

 maps ought not to be on one scale, for the reason that, while one certain part 

 of the continent is comparatively destitute of interest, over large tracts of country, 

 others crowd into a small space a gn at variety and even confusion of details. 

 They should, however, be upon multiples or fractions of a common unit. As a 

 bare suggestion I would mention scales of tyooooo ^^^ eFo^ooo ^^'" these re- 

 spectively It is even probable that particular sections would -require still 

 larger ones. The districts of country to be included in these regional maps 

 will necessarily form a subject of particular consideration. Entire hydrograph- 

 ical basins, as a general rule, afford the most homogeneous features, and should 

 therefore be adopted unless other reasons interfere. In the geological series, 

 for instance, it may be necessary sometimes to exhibit both sides of a mountain 

 range instead of vallies bounded by water-sheds. This class of maps will be 

 particularly adapted to natural history and the exhibition of physical phenomena. 



2d. A second series, in which the same scales and topography should be used, 

 but in which the divisions should be political, will be needed for another class 

 of subjects, such as population, education, agriculture, and generally all those 

 growing out of the relations of man in society. 



3d. Besides these there is requisite a map of the continent on a large scale, 

 certainly not less than 3000000- ^^ should include the entire arctic regions, 

 with the eastern part of the continent of Asia and the intermediate islands, the 

 islands of the Gulf of Mexico and the Caribbean sea, and the northern skirt of 

 South America. This, like the first, should consist chiefly of the hydrography, 

 giving only the chief mountain chains, or, at most, just indicating the lower 

 water sheds. Upon it the results of the former should be generalized. Sections 

 and profiles should, of course, accompany the ma2>8. 



