Geology of Martha’s Vineyard. 247 
also, of the cliffs of gypsum 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 
inthe lower Fresh Water Formations? If so, it forms a 
continuation of the vast tertiary formations, stretching 
through 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 
reat 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 oes 
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 hot 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, 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, wh ich I have never 
seen upon the continent: but it was not the season o 
Owers, 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, 
believe, undescribed. Very many of the bowlder stones 
Contain, on their surface, large quantities of the elegant 
rera chrysophthalma : —a lichen very rare 10 ron eee 
of New-England. Associated with this, is dburdarce of 
