146 Generation of Sulphur in 



No. 19 is a red clay dredged on the I3th March 1874, in 

 2600 fathoms, lat. 42 42' S., long. 134 10' E. Along with the 

 mud a large quantity of manganese nodules was brought up. 



No. 20 is a radiolarian ooze from the North Pacific, lat. 

 12 40' N., long. 152 i' W., depth 2900 fathoms. 



Nos. 21 and 22 are again samples of globigerina ooze from 

 the Atlantic and the Pacific respectively. These samples 

 differ from Nos. 12 and 13 inasmuch as the Pacific sample 

 now contains more sulphur than the Atlantic one. 



No. 23 is the insoluble residue left after treating a nodule 

 from the same locality as No. 2 with hydrochloric acid and 

 ferrous chloride. The difference is very remarkable. In 

 No. 2 the sulphur was not determined that is, the barium 

 sulphate produced by its oxidation was not weighed; but 

 it was one of these samples which showed that the amount 

 present was so appreciable that it was worth while determining 

 it as accurately as possible, so that it is certain that it must 

 have contained at least an average amount. In the case of 

 the natural nodule (No. 2) the weight of chloroform residue 

 per 100 grammes substance was 29 milligrammes; in the case 

 of the extracted nodule No. 23 it is 2 milligrammes, and the 

 weight of sulphate of barium is put down as i decimilligramme. 

 In fact, the sulphur in the nodule had disappeared under 

 the treatment. 



No. 24 is from Loch Fyne, in 87 fathoms, opposite Otter 

 House, and a little further up the loch than the station No. 6, 

 but both of them in the outer loch, as opposed to No. u, 

 which is in the upper and semi-enclosed basin. The contrast 

 between No. 24 and No. n is remarkable. In the upper 

 basin the amount of the chloroform residue per 100 grms. 

 substance was 74 milligrms., and 10 milligrms. of it was sulphur. 

 In the outer loch there were only 17 milligrms. of residue 

 and i milligrm. sulphur. 



No. 25 is a very remarkable white clay from the bottom 

 of Loch Ness, and therefore a fresh-water formation. It 

 occurs in a small area opposite Urquhart Castle, and in various 

 depths, often covered by a thin layer of peaty substance; 

 but in some places, in depths of about 30 fathoms, the sounding- 

 tube brings up the white clay alone. It was observed also 



