4:30 
THE VOYAGE OF H.M.S. CHALLENGER. 
15. Red Clay. — Station 252. 
Lat. 37° 52' N., long. 160° 17' W., 2740 fathoms (Brazier). 
Portion soluble in Hydrochloric 
Acid — 4 6 '40 
Portion in.soluble in Hydrochloric 
Acid = 50 '00 
Loss on ignition after drying at 230° Fahr., 
3-60 
Alumina, ..... 
5-23 
Ferric oxide, ..... 
. 13-14 
Calcium phosphate, .... 
small trace 
Manganese oxide, .... 
. trace 
Calcium sulphate, .... 
0-51 
Calcium carbonate, .... 
2-22 
Magnesium carbonate. 
0-41 
.Silica, ..... 
. 24-89 
^Alumina, ..... 
7-85 
Ferric oxide, .... 
2-60 
Lime, ..... 
1-50 
^lagnesia, ..... 
0-35 
Silica, ..... 
. 37-70 
100-00 
16. Red Clay. — Station 253. 
Lat. 38° 9' N., long. 156° 25' W., 3125 fathoms (Brazier). 
Portion soluble in Hydrochloric ) 
Acid -45 -69 i 
- i 
Portion insoluble in Hydrochloric ) 
Acid = 49-81 } 
Acid — 45*32 
Portion insoluble in Hydrochloric! 
Acid -50-1 8 r 
Loss on ignition after drying at 230° Fahr., 
4-50 
Alumina, . . . . 
8-31 
Ferric oxide, .... 
7-95 
Calcium phosphate. 
0-19 
Manganese oxide, .... 
0-65 
Calcium sulphate, .... 
0-37 
Calcium carbonate, .... 
0-92 
Magnesium carbonate. 
2-70 
L Silica, 
. 24-70 
f Alumina, ..... 
7-75 
Ferric oxide, .... 
3-88 
Lime, ..... 
0-28 
Magnesia, ..... 
0-60 
, Silica, ..... 
. 37-40 
Led Clay. — S tation 256. 
100-00 
'. 154° 56' W., 2950 fathoms (Brazier). 
Loss on ignition after drying at 230° Fahr., 
4-60 
Alumina, ..... 
6-00 
Ferric oxide, .... 
9-77 
Calcium phosphate. 
0-48 
Manganese oxide, .... 
0-68 
Calcium sul[ihate, .... 
0-42 
Calcium carbonate, .... 
1-69 
Magnesium carbonate. 
1-33 
t Silica, . . 
. 24-95 
|- Alumina, .... 
. 11-37 
Ferric oxide, .... 
2-00 
Lime, ..... 
1-14 
Magnesia, ..... 
0-85 
. Silica, ..... 
. 34-82 
100 00 
