Contents xxv 



PAGE 



Humboldt's explanation of the cold water on the 

 Peruvian coast postulated an impossibility. 



Similar mistake made in regard to cold water 

 occurring on the Atlantic coast of North America. 



If the cold water found on the New England coast 

 were furnished by a surface current from the coast of 

 Labrador that current, in order adequately to pres. 

 its temperature as the latitude decreases, must neces- 

 sarily have a velocity and a volume which would make 

 it an important assistance to south-bound coasting 

 vessels and a correspondingly serious hindrance to 

 those bound north. In the official Sailing Directions 

 mariners are not advised how to take best advantage 

 of this current on the southward course or how best 

 to avoid its influence on the northward course. More- 

 over, no independent hydrographic evidence is given 

 of the existence of any such current. 



6. ON THE OCCURRENCE OF SULPHL-R IN* MARINE MUDS 

 AND NODULES, AND IT-; BEARING ox THEIR MODE OF 

 FORMATION. [From Proc. Roy. Soc. Edin. 1890, 



Vol. xvin. pp. 17-39] -133 



This paper gives an account of the distribution, 

 the chemistry and the natural history of the ochreous 

 submarine deposits. of which the Manganese nodules 

 are the best known example. 



They were discovered westward of the Canary 

 Islands, in the first section of the voyage of the 

 "Challenger," and were proved to be aggregations of 

 the materials at the bottom of the sea chemically 

 metamorphosed. 



In June. i.S;^ i: XivhipeluRO of the A/o: 



concretions were tound perforated by worms, and the 

 inside ol manv of the 1. black by a 



dep . . . i u 



I on me thus earlv tli.it 

 th- submarine Ol hi :M m KHI 



:n I < 



06, 



Scotland, bv llr d that, 



v deep 

 . 



