86 On the Silurian System. 



So much has lately been presented to the public, either through 

 the newspapers, journals, or lectures, which I consider demon- 

 strably incorrect, that 1 can hardly, consistently with my love of 

 true science, remain an inactive observer of the consequent per- 

 version of the public mind. Unfortunately it is difficult if not 

 impossible to discuss sucli subjects without a resort to language 

 and ideas, which are too technical and abstruse for persons who 

 have not made chemistry and electricity an object of study. I 

 have however prepared a series of essays, in which the causes of 

 storms are stated, agreeably to my view of this important bragich 

 of meteorology. 



Art. XIII. — On the Silurian System, with a Table of the Strata 

 and Characteristic Fossils ; by T. A. Conrad. 



The geological structure of the territory of the U. States is be- 

 ginning to be fairly understood, through the active exertions of the 

 State geologists. We no longer confine ourselves to the vague terms 

 of transition and grauwacke, but are aware that many distinct for- 

 mations have been so designated. Prof. Eaton has long since given 

 names to some of these, which have been found useful, and would 

 have been much more so, had the fossils been collected in sufficient 

 numbers, and with great care to preserve their stratigraphical re- 

 lations. But this is a work of time and labor, and could not be 

 expected of an individual who had other duties to perform, and 

 at a period when the transition with its beautiful fossils, and other 

 most interesting history were almost wholly neglected even in 

 Europe? Taking a glance at the geology of the United States, 

 we find the Silurian system of Murchison spread over the greater 

 portion of New York, Ohio, Indiana, Kentucky, and Tennessee, 

 and terminating on the south in the mountainous or rather hilly 

 region of North Alabama. In the vicinity of Florence and Tus- 

 cumbia we find the Oriskany sandstone, (as designated in the New 

 York reports,) a rock very easily recognized by its casts and im- 

 pressions of large brachiopodous bivalves, quite unlike, as a group, 

 to any fossils above or below them. In Europe, a rock termed 

 old red sandstone separates the Silurian from the carboniferous sys- 

 tems, and fortunately I have detected the same rock, and with its 



