454 
THE VOYAGE OF H.M.S. CHALLENGER. 
77. Pumice. — Station 246. 
Portion soluble in Hydrochloric ■! 
Acid -32-60 J ' 
Portion insoluble in Hydrochloric \ 
Acid -61 -50 / 
ng. 178° 0' E., 2050 fathoms (Brazier). 
Loss on ignition after drying at 230° Fahr. , 
5-90 
Copper, ..... 
small trace 
Alumina, ..... 
2-50 
Ferric oxide, .... 
7-30 
Calcium phosphale, 
0-20 
Manganese oxide, .... 
4-56 
■{ Nickel, ..... 
small trace 
Cobalt, ..... 
Calcium sulphate, .... 
0-60 
Calcium carbonate, .... 
1-94 
Magnesium carbonate, 
2-00 
Silica, ..... 
. 13-50 
( Alumina, ..... 
6-00 
1 Ferric oxide, .... 
5-20 
Lime, ..... 
1-70 
1 Magnesia, ..... 
0-54 
1 Silica, ..... 
. 48-06 
100-00 
Note. — Pieces resembling pumice in a disintegrating state; as received, that is to say dry, the material floated in water 
for a time but afterwards sank. 
78. Pumice. — Station 286. 
Lat. 33° 29' S., long. 133° 22' W., 2335 fathoms (Brazier). 
Portion 
soluble in Hydrochloric 
Acid — 56 -27 
}- 
Portion insoluble in Hydrochloric 
Acid — 39 -23 
}- 
Loss on ignition after drying at 230° Fahr., 
4-50 
C Copper, 
trace 
Alumina, 
6-00 
Ferric oxide. 
11-00 
Calcium sulphate, . 
mere trace 
Manganese oxide, . 
5-70 
Nickel, 
ti-acc 
Cobalt, 
trace 
Calcium sulphate, . 
0-25 
Calcium carbonate, . 
1-90 
Magnesium carbonate, 
3-02 
^ Silica, 
. 28-40 
f Alumina, 
3-40 
Ferric oxide, , 
5-25 
Lime, 
1-36 
Magnesia, 
0-60 
t Silica, 
. 28-73 
100-00 
Note. — F our small pieces of matter (three soft and one hard) resembling pumice. 
79. Pumice. — Station 184. 
Lat. 12° 8' S., long. 145° 10' E., 1400 fathoms (Renard). 
I. 1-5321 grmn. of substarice dried at 110° C., fused with the carbonates of soda and potash, gave 0-0260 
gnn. of water, 0 7747 grin, of silica, 0 0122 grm. of titanic acid, 0-1578 grm. of alumina, 0 0757 grm. of 
[•croxide of iron, 0-0021 grm. of protoxide of manganese, 0-1422 grm. of lime, 0-3490 grm. of pyro- 
filiosphate of magnesia » 0-1 420 grm. of magnesia. 
( 
1 
I 
J 
( 
