THE VOYAGE OF H.M.S. CHALLENGER. 
4.)0 
68. Volcanic Mod. — Station VHb. 
Lat. 28“ 41' N., long. 16° 6' W., 640 fathoms (Brazier). 
Portion 
Portion 
soluble in Hydrochloric 
Acid -62 '98 
}- 
insoluble in Hydrochloric 
Acid — 32 08 
}- 
Loss on ignition after drying at 230° Fahr., 
f Alumina, .... 
Ferric oxide, 
Calcium phosphate, . 
. Calcium sulphate, . 
Calcium carbonate, . 
Magnesium carbonate, 
Silica, .... 
' Alumina, .... 
Ferric oxide, 
- Lime, .... 
Magnesia, .... 
Silica, .... 
4- 94 
5- 91 
7-02 
0-52 
105 
35-68 
2-04 
. 10-76 
4- 30 
5- 38 
2-58 
0-65 
. 19-17 
100-00 
Note. — W hen treated with dilute hydrochloric acid this substance evolved a perceptible tarry odour. 
69. Volcanic Mud. — S tation VIIt. 
Lat. 28° 42' N., long. 17° 8' W., 1750 fathoms (Brazier). 
Portion soluble in Hydrochloric 
Acid = 68 -57 
Portion insoluble in Hydrochloric 
Acid -25 -13 
Loss on ignition after drying at 230° Fahr. , . 6-30 
.'Alumina, . . . . . .5-71 
Ferric oxide, ..... 7-14 
Calcium phosphate, .... good trace 
— ■ Calcium sulphate, . . . . .1-15 
Calcium carbonate, . . . . .41-43 
Magnesium carbonate, . . . .1-43 
Silica, . . . . .11-71 
'Alumina, . . . . . .3-71 
Ferric oxide, . . .3-43 
= -1 Lime, . . . • .1-43 
Magnesia, ...... 0-72 
i. Silica, . . . . . .15-84 
100 00 
Note.— W hen treated with dilute hydrochloric acid this substance evolved a perceptible tarry odour. 
70. Volcanic Mud. — S tation VIII. 
Lat 28° 3' 15" N., long. 17° 27' W., 620 fathoms (Brazier). 
Portion 
soluble in Hydrochloric 
Acid -66 -23 
} 
i’ortion 
insoluble in Hydrochloric 
Acid — 27 -65 
} 
Loss on ignition after drying at 230° Fahr., 
6-22 
Alumina, 
5-00 
Ferric oxide, 
. 11-69 
Calcium phosphate. 
large trace 
Manganese oxide. 
trace 
Calcium sulphate, . 
0--27 
Calcium carbonate, . 
. 32-22 
Magnesium carbonate, 
0-83 
Silica, . 
16-22 
Alumina, 
4-22 
Ferric oxide. 
3-77 
Lime, 
1-44 
.Magnesia, 
0-22 
Silica, 
. 17-90 
I 
J.. 
it 
If. 
t 
> 
0 
I 
\ 
100-00 
