Valley of lie Mh?issippi 



36 



nous or extraordinary is that which I now propose to consider, viz, : 

 that the climate of the Valley of the Mississippi is much warm- 

 er, under similar parallels of latitude, than that of the Atlantic 

 coast. This was first advanced, as we shall presently discover; 

 by Mr. Jefferson, and was afterwards advocated by Volney, Wil- 

 liamson, and others. The arguments adduced in its support ap- 

 peared so plausible, that it was received as an axiom by almost all 

 subsequent writers upon the western country. I must however 

 remark, that Dr. Drake and Mr. Darby,* authors of great merit, 

 have each combatted this theory, as opposed to fact and observa- 



In common with many others, I adopted this opinion, in conse- 

 quence of the high reputation of its advocates, and without the least 

 examination of the facts upon which it rested. I always, however, 



serve a more minute investigation, and a more ample explanation. 

 Accordingly upon rriy removal to the western country, I determin- 

 ed to direct my attention to this subject, and during my residence 

 there, I obtained more accurate information concerning its climate 

 than has hitherto been published. On comparing the results of my 

 observations with similar ones on the Atlantic coast, I was furnish- 

 ed with ample testimony to prove the similarity, in this respect be- 

 tween these two different se< ites. These ob« 



previous to doing this it will first be necessary to examine, and ex- 

 pose the fallacy of, the arguments adduced in support of the supe- 

 rior temperature of the climate of the valley of the Mississippi. 



It is, I believe, to Mr. Jefferson that we are originally indebted 

 for this theory, in regard to the difference in the temperature of the 

 climate in various parts of the United States. In his " Notes on 

 Virginia," this learned author observes : 44 It is remarkable that, 

 proceeding on the same parallel of latitude westwardly, the climate 

 becomes colder, in like manner as when you proceed northwardly. 

 This continues to be the case, till you attain the summit of the Al- 

 leghany, which is the highest land between the ocean and the Mis- 

 sissippi. From thence descending in the same latitude to the Mis- 

 sissippi, the change reverses ; and, if we may believe travellers, 

 it becomes warmer there than it is in the same latitude on the sea- 

 side. Their testimony is strengthened by the vegetables and ani- 



