Of the famous rock in Horeb, said to bethat which at the touch of Moses ’ rodfurnished water to the Israelites in the wil-derness, Dr. Shaw a gives us the followingaccount: “ It is a block of granite marble“ about six yards square, lying tottering as« it were in the middle of the valley, and“ seems to have belonged to Mount Sinai,« which hangs in a variety of precipices“ all over the plain.” I am informed thatblocks of Granit extend for more than onehundred miles on the south of Lake Huron ,in North America , and appear in islandstwelve miles from its margin.

Granit bowlders, therefore, are not ofpartial occurrence, nor is the theory tenable,which supposes those found in the North ofGermany , to have slid thither upon theice.

A late naturalist 1 *, who, dying in thefullness of years, 'left behind him a namemuch too respectable to prevent his errorsfrom being contagious, advanced a veryextraordinary hypothesis, to explain the

* Shaw’s Travels, p. 352.b Deluc’s Geol. Tr. vol. i.