CHA PPE, ELE. 
THE GULF-STREAM. 
The Range of the ‘Porcupine’ Temperature Observations.—Low 
Temperatures universal at great Depths.—The Difficulty of in- 
vestigating Ocean Currents.—The Doctrine of a general Oceanic 
Circulation advocated by Captain Maury and by Dr. Carpeuter.— 
()pinion expressed by Sir John Herschel.—The Origin and Exten- 
sion of the Gulf-stream.—The Views of Captain Maury; of Pro- 
fessor Buff ; of Dr. Carpenter.—The Gulf-stream off the Coast of 
North America.—Professor Bache’s ‘Sections.—The Gulfstream 
traced by the Surface Temperatures of the North Atlantic —Mr. 
Findlay’s Views.—Dr. Petermann’s Temperature Charts.—Sources 
of the underlying Cold Water.—The Arctic Return Currents.— 
Antarctic Indraught.—Vertical Distribution of Temperature in 
the North Atlantic Basin. 
AL the temperature investigations carried on in 
H.M.SS. ‘ Lightning’ and ‘Porcupine’ during the 
years 1868-69 and 1870, with the exception of a 
series of observations already referred to taken in 
the Mediterranean under Dr. Carpenter’s direction 
in the summer of 1870, were included within an area 
nearly 2,000 English miles in length by 250 in 
width, extending from a little beyond the Féroe 
Islands, lat. 62° 30’ N., to the Strait of Gibraltar, 
lat. 36° N. 
The greater part of this belt may be described as 
