CHAPTER Vin 



1877-1880 

 THREE CRUISES OF THE BLAKE 



Agassiz's interest in oceanographic exploration, which 

 in its broadest aspects was to form the chief interest of 

 his later life, dates from a short voyage, soon after his 

 arrival in the United States, made with his father in a 

 little coast survey vessel. This came near being his last 

 as well as his first probing of the ocean, for after fall- 

 ing down a hatchway he was laid out apparently dead 

 on the sofa in the saloon. 



Two Italians, Marsili and Donati, appear to have 

 been the first men to employ a dredge for collecting 

 scientific specimens. About 1750, they used a common 

 oyster dredge in shallow water. In 1779, 0. F. Muller, 

 the Danish naturalist, invented a special dredge for 

 scientific work with which he studied the bottom of the 

 sea to a depth of thirty fathoms. Among the pioneers 

 in oceanography may be mentioned Forbes, Torell, the 

 elder and younger Sars, Alphonse Milne Edwards, and 

 in America, Pourtales. 



As a result of deep-sea work in the iEgean in 1841, 

 the brilliant naturalist, Edward Forbes, had propounded 

 the theory that animal life at the bottom of the sea was 

 limited to a depth of three hundred fathoms. This was 

 the generally accepted belief up to the late sixties, 

 though a few naturalists, mindful of certain half-for- 

 gotten facts, attempted in vain to question the authority 



