Animadversions on Mr. Genet's Memorial, fyc. 79 



exclusively sandstone. The descent to the Tennessee valley, 

 is about a mile in length, and very steep. On the side of 

 the mountain the rock is chiefly limestone. The valley of 

 the Tennessee here extends into the state of Tennessee. It 

 is a beautiful, fertile and highly cultivated country, in the 

 midst of which, is the flourishing and beautiful village of 

 Huntsville. In the south part of Tennessee south from 

 Nashville there are high mountains of limestone on some of 

 which are the most stately cedars. On the tops of some of 

 these mountains and also on the tops of the mountains in 

 Alabama, we find occasional ridges of very recent clay slate. 

 The specimens of petrified shells I send you, were taken 

 from a hill about thirty miles north from Nashville. The 

 slate decomposes and turns into clay, and the shells tumble 

 to the bottom. Yours, 



Prof. Silliman. William S. Porter. 



Art. XIV. — Animadversions on Mr. Genefs Memorial on 

 the Upward forces of Fluids, and on his " reply to Dr. 

 Jones, in the Franklin Journal;'''' by Thomas P. Jones, 

 M. D., Editor of the Franklin Journal, and Professor of 

 Mechanics in the Franklin Institute, of the State of Penn- 

 sylvania. 



" THE BASELESS FABRIC OF A VISION." 

 To the Editor of the American Journal of Science and Arts. 



Sir — Editors, it appears, are sometimes " not only witty 

 themselves, but the cause of wit in others." Thus it seems 

 that a note of yours, called forth the reply of Mr. Genet 

 to my remarks on his Essay ; and I can assure you that but 

 for the importance given to the subject of that memorial, by its 

 analysis in your Journal, I should have spared myself a very 

 large proportion of the labor which I have now undertaken ; 

 but when even " airy nothings" obtain " a local habitation 

 and a name," they derive from this circumstance, an arti- 

 ficial importance which no other could have obtained for 

 them. 



The readers of your Journal are informed through the 

 medium of Mr. Genet's communications, that I have, in the 

 Franklin Journal, controverted this opinion of that gentle- 



