Vol. V, pp. 59-96, PL. 21 July io, 1893 



THE 



NATIONAL GEOGRAPHIC MAGAZINE 



THE NATURAL BRIDGE OF VIRGINIA 



BY 

 CHARLES D. WALCOTT 



The Natural Bridge of Virginia is one of those striking geo- 

 graphic features of America which, like Niagara falls and many 

 other natural features, will in time disapjiear under the action 

 of the agencies of erosion. The same forces that created, will 

 ultimatel}^ destroy them. In the case of Niagara, the rate of 

 wear of the j)latform over Avhich the water rushes has been 

 measured, and the rate of retreat of the falls of the stream is 

 known. Natural bridge is slowly but surely wearing away ; 

 and it appears to be desirable to record by i^hotographs and 

 notes the present condition of the bridge as a means of deter- 

 mining in the future the changes that occur from time to time. 

 For this purpose a set of photographs, with notes taken in 1891, 

 have been placed in the librar}^ of the Uftited States Geological 

 Survey. 



The present article includes a few observations on the origin 

 and the present condition of the bridge. The accompanying- 

 view (forming plate 21) is one looking northward through the 

 arch, and it accurately represents the condition of the bridge 

 and canyon at the time it was taken. It may be that a more 

 detailed description, with a full series of views, will be published 

 in the future. 



During the field season of 1891 I studied the rocks ex|)osed 

 along the channel of Cedar creek, a small tributary of the 

 James river in Rockbridge county, Virginia. The first strata 



9— Nat. aEoa. Mag., vol. V, 1893. (59) 



