Geology of Martha? s Vineyard. 247 



also, of the cliffs of gypsiim and sandstone in Nova Scotia, 

 and the enquiry arises whether that gypsum is not identical 

 with the same rock in the vicinity of Paris, where it occurs 

 in the lower Fresh Water Formations? If so, it forms a 

 continuation of the vast tertiary formations, stretching 

 thiough the eastern border of the United States, and em- 

 bracing some of the West-India Islands, and adds to them 

 an interesting link. Finally, if we carry this curve across the 

 Atlantic, it will pass not far from the northern extremity of 

 Great Britian, and include within it the tertiary formations of 

 England and France, and, indeed, of all Europe. The en- 

 quiry then, immediately suggests itself, can it be, that the 

 tertiary formations of Europe and of the United States, are 

 merely the extremities of the same vast basin ; the inter- 

 mediate parts of which, have been swept away by the 

 currents and waves of the ocean, or by some mighty catas- 

 trophe ? Whether such questions deserve any serious con- 

 sideration, or not, it is obvious, that there are facts enough 

 brought to light, to induce our geologists to subject those 

 parts of our country, hitherto called alluvial, to a thorough 

 re-examination. And there is reason to anticipate, as the 

 fruit of such researches, the discovery of many more beds of 

 gypsum, than are now known ; and also, of chalk ? If this lat- 

 ter substance exist immediately below Plastic Clay in Eng- 

 land and France, why may we not expect, that when the 

 same formation in this country is penetrated, chalk will 

 be found beneath it ? In England, the Plastic Clay is not usu- 

 ally more than 100 feet in thickness : but in Martha's Vine- 

 yard, (if it really exist there,) the ocean has already laid open 

 this formation nearly 200 feet in depth ; so that the bottom 

 of it might probably be reached without much difficulty. 



I visited the Vineyard in the early part of June; and the 

 season being unusually late, I am unable to say much of its 

 botany, if it be proper, in this place, to say any thing. A 

 species of oak exists abundantly there, which I have never 

 seen upon the continent: but it was not the season of its 

 flowers, or fruit ; and the leaves were but just opening, so 

 that I could determine nothing concerning the species. A 

 species of Ranunculus also occurs, which, is stemless, and, 

 1 believe, undescribed. Very many of the bowlder stones 

 contain, on their surface, large quantities of the elegant 

 Borrera chrysophthalma :— a lichen very rare in most parts 

 of New-England. Associated with this, is abundaoce of 



