THE 

 AMERICAN 



JOURNAL OF SCIENCE, &c. 



GEOLOGY, MINERALOGY, TOPOGRAPHY, &c. 



Art. I. — A memoir on the natural Walls, or solid dykes, 

 in the State of JVorth- Carolina; about which there have 

 been debates, whether they were basaltic, or of some other 

 formation ; by John Beck with, M. D. fellow of the 

 College of physicians in Mew-York, «^c. to Samuel XUich- 

 ell, M. D. ^ P. «^c. dated Salisbury, North Carolina^ 

 December 18, 1821. 



[Commimicated for this Journal.] 

 Dear Sir, 



X RECEIVED your letter of the 3rd of Oct. and have, agreea- 

 bly to your request, put up a set of the specimens taken 

 from the different basaltic walls in this neighbourhood, illus- 

 trative of their formation. You will probably receive them 

 shortly by one of the coasting vessels from Wilmington to 

 New- York. You also expressed a wish that I would com- 

 municate such information, connected with their history as 

 might be in my possession ; and referred me to several Volb. 

 of the Medical Repository, for what had been written upon 

 the subject. 1 had read and compared the descriptions 

 given by the Rev. Dr. Hail, and the Rev. Zach. Lewis, 

 with the walls themselves, and found them in many particu- 

 lars correct ; and I cannot perhaps better convey my own 

 views than by quoting occasionally from them. I shall not 

 however attempt to discuss with these gentlemen, the ques- 

 tion of their origin or nature : it is a matter so completely 

 VoL.V No. 1 1 



