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PAGE 



When heated they give off alkaline water with an 

 empyreumatic odour. 



The number of different elements contained in them 

 is large. 



Table of the results of the analyses of six different 

 samples . . . . . . . J 59 



Nodules from different localities differ in com- 

 position but those from the same locality have similar 

 composition. 



The Manganese is chiefly present as MnO 2 . 



Of the rarer metals Cobalt is the principal repre- 

 sentative. 



No. 8. MANGANESE NODULES IN LOCH FYNE. [From 



Nature. Oct. 10, 1878, Vol. xvm. p. 628] . . . 160 



It was believed by every member of the "Challen- 

 ger" expedition to have been established that the 

 Manganese nodules are to be found only in the greatest 

 depths of the ocean and to be absent in shallow water. 



When I proceeded in the summer of 1878 to explore 

 the waters round the coast of Scotland in the steam - 

 yacht "Mallard," of 95 tons, it was without any ex- 

 pectation of finding evidence to upset this conviction ; 

 yet it so happened that in the very first station which I 

 made, in the deepest part of Loch Fyne, the anchor 

 which I used brought up a mass of mud from a 

 depth of 104 fathoms in which Manganese nodules were 

 present in greater relative abundance than in any mud 

 brought from 2000 or 3000 fathoms in the open ocean. 

 Moreover, the anchor with this valuable load was 

 brought up at the end of a fine steel wire cord. Con- 

 sequently on 2ist September, 1878, the "Mallard" 

 scored a double record, namely, the discovery of Man- 

 ganese nodules in shallow water and the first use of 

 metallic cables in oceanographical work on the eastern 

 side of the Atlantic. Agassiz had used a metal cable in 

 1877 in American waters. 



My cable was a cord of one-tenth inch diameter con- 

 Og of thirty-five fine steel wires in strands. It was 

 manufactured for me by Messrs Siemens Brothers, and 

 I used it for four seasons with uniform success. At the 

 end of the last season it was called upon to lift a heavily 

 loaded anchor-dredge from deep water and it parted. 

 The cable and the dredge, both of which had served me 



