434 
THE VOYAGE OF H.M.S. CHALLENGEK. 
24. Red Clay. — Stutioii 9. Lat. 23° 23' N., long. 35° IT W., 3150 fathoms (Ilornung). 
I. 1 1459 grms. of substance dried at 110° C., fused with carbonates of soda and potash, gave 0‘6519 grm. of 
silica, 0'2323 gnu. of alumina, 0'1148 grm. of ferric oxide, 0‘0150 grm. of lime, 0’0293 grm. of mag- 
nesia, and 0'0770 grm. loss on ignition. 
II. 1'1162 grms. of substance dried at 110° C., treated with sulphuric and hydrofluoric acids, gave 0‘0219 grm. 
of potash, and 0 0092 grm. of soda. 
Silica, .... 
Alumina, .... 
Ferric oxide, 
Lime, .... 
Magnesiii, ..... 
Potash, .... 
Soda, .... 
Loss on ignition, 
Carium, manganese, and phosphoric acid. 
66-89 
20-28 
10-02 
1- 31 
2- 56 
1-91 
0-81 
6-72 
traces 
100-50 
25. Red Clay. — Station 29. Lat. 27° 49' N., long. 64° 59' W., 2700 fathoms (Renard). 
I. 1370 grms. of substance dried at 110° C., fused with the carbonates of soda and potash, gave 0-0513 grm. 
of water, 0-5774 grm. of silica, 0-2776 grm. of alumina, 0-0967 grm. of peroxide of iron, 0-1811 grm. 
of lime, 0-0815 grm. of pyrophosphate of magnesia = 0’0294 grm. of magnesia. 
II. 0 9872 grm. of substance, dried at 110° C., gave 0 0969 grm. of carbonic acid, 
III. 1-329 grms. of substance dried at 110° C., treated with hydrofluoric and sulphuric acid.s, gave 0-0416 grm. 
of the chlorides of potash and soda, 0-0769 grm. of chloroplatinate of potash = 0-0149 grm. of potash. 
and, by difference, 0-0095 grm. of soda. 
Silica, .......... 42-15 
Alumina, , . . . . . . . .20-27 
Peroxide of iron, . . • . . . . . .7-06 
Lime, .......... 13-22 
Magnesia, .......... 2-15 
Potash, . . . . . . . .1-12 
Soda, . . . ..... . . . .0-72 
Carbonic acid, . . . . . . . . .9-82 
■Water, .......... 3-75 
100-26 
26, Red Clay (after the finer parts had been washed away). — Station 281. 
Lat. 22° 21' S., long. 150° 17' W., 2385 fathoms (Hornung). 
0-3436 grm. of .sul)stance, dried at 100° C., lo.st 0-0297 grm. 
0-8375 ,, ,, ,, 0-0657 „ 
0- 8392 ,, „ „ 0-0698 ,, 
1- 1275 ,, ,, ,, 0-0933 ,, 
Mean loss on ignitioi 
— 8 -52 per cent. 
-7-81 „ 
-8-28 „ 
-8-27 „ 
- 8-22 
I. 0 3024 grm. of substance, dried at 100° C., fused with the carbonates of potash and soda in a porcelain tube, 
gave 0 01 94 grm. of water. 
II. 0 7694 grm. of sulwtance, dried at 100° C., gave 0-3333 grm. of silica, 0 1074 grm. of alumina, 0-1346 
grm. of peroxide of iron, 0-0459 grm. of lime, 0 1 258 grm. of pyrophosphate of magnesia = 0 04 5 3 grm. 
of magnesia. 
III. 0-4973 grm. of substance, dried at 100° C., treated at 140° C, in a closed glass tube with sulphuric acid, 
rcrjuiie<l 3-5 c.c. of permanganate of potash (1 c.c. of permanganate of potash = 0 04813 grm. of 
protoxide of iron), corresponding to 0 02 166 grm. of ]>rotoxide of iron. 
