432 THE POPULAR SCIENCE MONTHLY 
Havana, Cuba, in December, 1877, and remained on board until April, 
1878, exploring the Gulf of Mexico, and adjacent regions. Admiral, 
then Lieutenant Commander C. D. Sigsbee, U.S.N., was in command, 
and his ingenious inventions of sounding apparatus, trawls, etc., en- 
abled the expedition to accomplish unprecedented results. 
The second cruise of the Blake started from Washington on No- 
vember 27, 1878, with Captain J. R. Bartlett, U.S.N., in command, and 
throughout the winter of 1878-79 they cruised among the Windward 
Isles of the West Indies and over the Caribbean Sea, visiting Havana, 
Jamaica, Hayti, Porto Rico, St. Thomas, Santa Cruz, Montserrat, St. 
Kitts, Guadeloupe, Dominica, Martinique, St. Lucia, St. Vincent, 
Granadines, Grenada and Barbados, and gathering an immense collec- 
tion of animals from the depths of the ocean. 
‘The third and last cruise of the Blake was for the purpose of sound- 
ing the depths of the Gulf Stream. They started from Newport in 
June and cruised until August, 1880, running seven lines of sound- 
ings off the coast between Charleston and George’s Bank, which led to 
the discovery-that a plateau covered by water not more than 600 fath- 
oms deep extends from the Bahamas northward to Cape Hatteras, form- 
ing a vast triangular area of shallow water, the outer edge of which 
is from 300 to 350 miles out in the ocean from the coast of the South- 
ern Atlantic States. The Gulf Stream flows across this area on its 
course between the Straits of Bemini to Cape Hatteras, and the outer 
edge of this shallow bank is \; vere the North American continent rises 
abruptly from the depths of the flat floor of the ocean. The name 
“Blake Plateau” was most appropriately given by Alexander Agassiz 
to this extensive area of shallow water. 
During her three cruises the Blake made 350 soundings, deep-sea 
temperature observations, and trawl hauls yielding a phenomenally rich 
harvest of new and interesting marine animals. Among other things, 
the second cruise led to the discovery of a vast submarine valley, the 
“ Bartlett Deep,” extending for nearly 700 miles along the southern 
coast of Cuba toward Honduras. Twenty miles south of Grand Cay- 
man this great depression is 3,400 fathoms deep, so that the summits 
of the mountains of Cuba only 50 miles away are 28,000 feet above its 
somber trough. 
This experience upon the Blake was the most momentous event in 
Alexander Agassiz’s scientific life, for it gave him a taste for marine ex- 
ploration which was to dominate his future career. Without this he 
might have continued to be an embryologist and systematic zoologist, 
but he was destined to more conspicuous achievements as an explorer. 
Its effect upon the history of the Museum at Cambridge was also 
profound, for the output of museum publications had been so slow that 
at the end of 1877 only three volumes of the “ Bulletins ” and five vol- 
