4-28 
THE VOYAGE OF H.M.S. CHALLENGER. 
9. Red Clay. — Station 20. 
Lat. 18° 66' N., long. 59° 35' W., 2975 fathoms (Brazier). 
Portion soluble in Hydrochloric 1 
Acid -66-83 i 
Portion insoluble in Hydrochloric \ 
Acid = 35-72 / 
Portion soluble in Hydrochloric 
Acid = 50 -42 
}- 
Portion insoluble in Hydrochloric • 
Acid = 43-66 
Loss on ignition after drying at 230° Fahr., 
7-45 
Alumina, ..... 
. 12-28 
Ferric oxide, .... 
. 11-44 
Calcium phosphate, .... 
small trace 
■ Calcium sulphate, .... 
1-47 
Calcium carbonate, .... 
3-50 
Magnesium carbonate. 
2-14 
L Silica, ..... 
. 26-00 
Alumina, ..... 
7-28 
Ferric oxide, .... 
2-36 
. Lime, ..... 
1-18 
Magnesia, ..... 
0-50 
^Silica, ..... 
24-40 
100-00 
Red Clay. — Station 21. 
ag. 61° 28' W., 3025 fathoms (Brazier). 
Loss on ignition after drying at 230° Fahr., 
5-92 
Alumina, ..... 
7-04 
Ferric oxide, .... 
. 12-25 
Calcium phosphate. 
small trace 
■ Calcium sulphate, .... 
0-51 
Calcium carbonate, .... 
2-44 
Magnesium carbonate. 
3-48 
Silica, ..... 
. 24-70 
r Alumina, ..... 
5-51 
j Ferric oxide, .... 
6-73 
■| Lime, ..... 
0-81 
1 Magnesia, ..... 
0-41 
''Silica, ..... 
. 30-20 
100-00 
11. Red Clay. — Station 27. 
Lat. 22° 49' N., long. 65° 19' W., 2960 fathoms (Brazier). 
Portion soluble in 
Acid -44 -16 
Hydrochloric 
}- 
Portion insoluble in Hydrochloric 
Acid = 51 -59 
}- 
Loss on ignition after drying at 230° Fahr., 
4-25 
Alumina, 
6-50 
Ferric oxide. 
7-83 
Calcium phosphate. 
1-67 
Manganese oxide, . 
good trace 
Calcium sulphate, , 
. trace 
Calcium carbonate, . 
3-25 
Magnesium carbonate. 
1-13 
Silica , , 
. 23-78 
Alumina, 
. 10-19 
Ferric oxide. 
4-29 
Lime, 
1-61 
Magnesia, 
0-33 
Silica, 
. 35-17 
100-00 
