Page:Notes on the State of Virginia (1802).djvu/37

Rh The height of our mountains has not yet been eſtimated with any degree of exactneſs. The Alleghaney being the great ridge which divides the waters of the Atlantic from thoſe of the Miſſiſippi, its ſummit is doubtleſs more elevated above the ocean than that of any other mountain. But its relative height, compared with the baſe on which it ſtands, is not ſo great as that of ſome others, the country riſing behind the ſucceſſive ridges like the ſteps of ſtairs. The mountains of the Blue ridge, and of theſe the Peaks of Otter are thought to be of a greater height, meaſured from their baſe, than any others in our country, and perhaps in North America. From data, which may found a tolerable conjecture, we ſuppoſe the higheſt peak to be about 4000 feet perpendicular, which is not a fifth part of the height of the mountains of South America, nor one third of the height which would be neceſſary in our latitude to preſerve ice in the open air unmelted through the year. The ridge of mountains next beyond the Blue ridge, called by us the North mountain, is of the greateſt extent; for which reaſon they were named by the Indians the Endleſs mountains.

A ſubſtance, ſuppoſed to be pumice, found floating on the Miſſiſippi, has induced a conjecture, that there is a volcano on ſome of its waters: and as theſe are moſtly known to their ſources, except the Miſſouri, our expectations of verifying the conjecture would of courſe be led to the mountains which divide the waters of the Mexican Gulph from thoſe of the South Sea; but no volcano having ever yet been known at ſuch a diſtance from the ſea, we muſt rather ſuppoſe that this floating ſubſtance has been erroneouſly deemed pumice.