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A ‘ globigeriiia-ooze/ contaiuiug many pelagic foraminifera of
the genera Glohigerina, Orbulina, Pulvinulina, a.n6 Sphoeroidina ;
many coccolitlis aud rhabdoliths.
Amorphous clayey matter Avith oxide of iron. Small particles
of sanidine, augite, pnmice, magnetite, &c. A fcAv grains of manganese
peroxide.
No. 13.—Station 16. Lat. 20° 39' N. ; Long. 50° 33' W.
Depth, 2,435 fathoms. Bottom temperature, 1°’7 C. Chemical
composition :—
Loss on ignition after drying a t 230° F.
Portion soluble in
liydrocliloric acid
= 78-40.
Portion insoluble
in liydrocliloric
acid = 12-00.
A l u m i n a ................................................................
Ferric o x i d e ..........................................................
Calcium p h o s p h a te ........................................Small
Calcium s u l p h a t e ...............................................
Calcium c a r b o n a te ...............................................
Magnesium c a r b o n a te .........................................
S i l i c a ......................................................................
A l u m i n a ..........................................................
Ferric o x i d e .....................................................
L i m e ................................................................
M a g n e s ia ...........................................................
Silica . . . . ■..........................................
9-60
4-00
7-10
traces.
2-32
52-22
0-76
12-00
2-96
0-64
0-40
8-00
100-00
A ‘ red clay,’ containing amorphous clayey matter with oxide
of iron, and many small particles of magnetite, felspar, pnmice,
and hornblende. A few grains of manganese peroxide.
Many pelagic foraminifera of the genera Globigerina, Orbulina,
Sphoeroidina, and Pulvinulina. Coccoliths and rhabdoliths.
The dredge brought np five small round manganese concretions
abont the size of marbles, and three sharks’ teeth of the genus
Lamna with a slight coating of manganese peroxide.
No. 14.—Station 17. Lat. 20° 7' N. ; Long. 52° 32' W.
Depth, 2,385 fathoms. Bottom temperature, l°-9 C. Chemical
composition :—
Loss on ignition after drying,at° 230 P .................................................... 6-84
A l u m i n a ................................................................. 2-69
Ferric o x i d e ........................................................... 9 'ID
Calcium p h o s p h a te ............................................... 1 '74
Calcium sulpha te..................................................... 0-81
Calcium c a r b o n a t e .......................................................58-40
Magnesium c a r b o n a t e ......................................... 0-68
S i l i c a .................................................................
Portion soluble in
hydrochloric acid
= 83-44.
Portion insoluble
in hydrochloric
acid = 9-72.
10-07
Insoluble residue, principally alumina and
ferric oxide, with s i l i c a .............................. 9-72
100-00
A ‘ red-clay ’ containing amorphous clayey matter Avith oxide
of iron, and many small particles of sanidine, augite, magnetite,
and quartz. A few grains of manganese peroxide. Many pelagic
foraminifera of the genera Globigerina, Pulvinulina, Sphceroi-
dina, &c. ; coccoliths and rhabdoliths.
No. 15. Station 18. March 10th. Lat. 19° 41' N ; Long. 55°
13' W. Depth, 2,675 fathoms. Bottom temperature, ^l°-6 C.
Chemical composition :—
Loss on ignition after drying- at 230° F.
Alumina
Ferric oxide .
Calcium phosphate
Calcium sulphate
Portion soluble in
hydrochloric acid 1
= 60-00.
Portion insoluble'
in hydrochloric
acid = 32-26.
76
25
-37
-42
52
11-
0--
0-
1-
22-
7-
2-
0-
0-
Calcium c a r b o n a t e ...................................................... 15-78
41
-25
00
50 -57
■38
Magnesium carbonate
S i l i c a .......................
Alumina . . . .
Ferric oxide . . .
L i m e .......................
Magnesia
S i l i c a .............................................................................. 21-80
100-00
A ‘ red-clay ’ containing amorphous clayey matter, and small
particles of augite, felspar, hornblende, aud magnetite. A fcAv
grains of manganese peroxide. A fetv broken tests of pelagic
foraminifera, còccolitbs and rhabdoliths.