270 THREE CRUISES OF THE “ BLAKE." 
The explorations of the “ Blake” have extended our know- 
ledge of the bottom deposits of our coasts so as to include the 
Gulf of Mexico and the Caribbean. Within the Caribbean, the 
explorations of the “ Blake" have been supplemented by those 
of the “ Albatross.” In addition to the soundings of the 
* Blake" on the eastern edge of the Gulf Stream, and in the 
basin of the western Atlantic between the West India Islands, 
Bermudas, and New York, we have a few observations made by 
the “Challenger.” The work of the “ Blake” on the south- 
ern coast of New England has been materially advanced. by the 
continuous explorations of the United States Fish Commission 
during the past years. 
From these different sources we may obtain a moderately 
complete sketch of the character of the bottom deposits of the 
western Atlantic, and of the adjoining enclosed seas. For the 
sake of convenience, we shall describe in order the deposits pro- 
cured from the Gulf of Maine, and from the eastern coast as far 
south as Cape Hatteras; next, the specimens from the coast 
south of Hatteras, to latitude 31° 48’ N., off the northern ex- 
tremity of the Bahamas; then those of the Gulf of Mexico, 
of the Caribbean, and of the West India Islands, closing with 
the description of the deposits of the basin of the western At- 
lantic. I shall transcribe descriptions from Mr. Murray’s report 
on the deposits collected by the “ Blake,” adding observations 
of general interest from the soundings of Pourtalés and of 
the Fish Commission, and from my own. 
“ The deposits procured in the Gulf of Maine, and along the east 
coast of the United States as far south as Cape Hatteras, consist of 
blue or gray colored muds and sands. The muds are darker-colored 
when wet, earthy, plastic, more or less granular, and coherent, drying 
into hard lumps. These deposits are chiefly made up of the débris of 
the land of the North American continent. 
* In 1,240 fathoms and Lat. 38° 34' N., off the coast of New Eng- 
land, the ‘ Challenger’ dredged many rounded and angular pebbles of 
milky and hyaline quartz, fine-grained quartzites, feldspathic quartz- 
1 The sandy deposits are found only examined by the * Blake ” along our east- 
within 100 fathoms. They lie between ern coast ате 1,994 and 1,186 fathoms, 
the coast and the inner edge of the Gulf which are situated between thirty and 
Stream. The greatest depths of the tract forty miles outside the 100-fathom line. 
