Editorial Miscellany. 18o 



them. No one will deny that the nebula and the comet will constantly 

 come into contact ; and were we acquainted with all the materials so 

 meeting, it would be a comparatively simple problem for the chemist 

 to determine what compounds would result, and for the physicist to 

 show in what state, gaseous or otherwise, they would afterward 

 remain. Both these questions require to be answered satisfactorily 

 before it is possible to declare whether the celebrated hypothesis of 

 Laplace is or is not the true key to the solution of the formation and 

 history of the solar system ; and for these answers, at the present, it 

 waits. 



EDITORIAL MISCELLANY. 



ARCHiEOLOGY.— From a recent article in Harper's Magazine, we re- 

 produce in substance several interesting statements concerning the 

 antiquities of the Mississippi Valley : Near Osceola, Arkansas, in the 

 vicinity of a great artificial mound, is a level area of ten acres paved with 

 adobe, and supposed to have been constructed and used as a threshing 

 floor, in connection with bins or storehouses, whose remains are still to 

 be observed in the vicinity. The paved floor is covered with black 

 loam to a depth of two and a half feet, and experiments are being 

 made with a view of approximating the age of the works by a method 

 heretofore suggested in these columns, namely : measuring, by repeated 

 observations and experiments, the annual deposit of loam from decay- 

 ing forest vegetation in given districts. 



The old river channels of the Mississippi, formed by successive 

 changes of the current, are to be distinctly traced between Memphis 

 and the ridge 40 miles west, at whose base flows the St. Francis river. 

 Everywhere upon the intervening lowland are observed the mounds 

 and aguadas of the ancient people, from which the inference is 

 drawn that they were built after the Mississippi had reached a 

 channel five miles west of its present bed. These remains extend 

 .southward only as far as Baton Rouge, and, assuming that within a 

 comparatively recent geological period the Gulf of Mexico extended 

 far up the present valley of the Mississippi, it is inferred that Natchez 

 or Baton Rouge stand at what was in the Mound-Builders' era the head 

 of this extension of the Gulf^a present distance of three hundred 

 miles. Calculating the annual sedimentary deposit at two hundred 

 linear yards, and assuming this rate to have been uniform, a period of 

 three thousand years is supposed to have elapsed since the abandon- 

 ment of these works. 



