226 APPENDIX. 



great similarity to the residue of the combustion of wood, is 

 designated in Germany by the name of asche (ashes). 

 These characters, when taken into connection, appear to us 

 to correspond so well with those observed on the Wassemon, 

 on the Missisippi, and throughout the country between Rock 

 River and Prairie Du Chien, that we feel strongly induced 

 to consider the limestone of this country as analogous to that 

 observed by Mr. Freisleben. This limestone is, by some 

 European continental geologists, referred to the Lias of 

 English geologists ; but we would rather refer it, with 

 Messrs. Conybeare and Phillips, to the newer magnesian or 

 conglomerate limestone of England. To this we think it 

 has the strongest analogy. It is probably connected, as we 

 have already intimated, with the limestone situated above the 

 coal fields of Wheeling and Zanesville. It extends over 

 those parts of Ohio and Indiana where salt has been found. 

 It is observed cellular, cavernous, &c., on the banks of the 

 Wassemon. It is connected with real calcareous ashes on 

 the Missisippi. The presence of the oolite which was ob- 

 served here in a single spot, does not militate against the 

 position which we have taken, as we find it stated by Cony- 

 beare and Phillips (page 302) on the authority of Mr. Wynch, 

 that the magnesian limestone is occasionally oolitic. It pre- 

 sents, in many of its points, the characters of the rauch- 

 wacke, and especially the cellular or cavernous structure. 

 It is seldom found very abundantly strewed with organic 

 remains. Its color is the pale buff, passing to the ash-grey. 

 In fine, the more attentively we examine it, the more closely 

 do we find it to connect itself with the formations of Thurin- 

 gen, and with those which cover so extensive a part of Eng- 

 land, and more particularly with that observed in Yorkshire 

 by Professor Buckland ; offering thus, as it appears to us, 

 a beautiful confiraiation of the analogy established between 



