CHAP, v.] 



GENERAL CONCLUSIONS. 



321 



Loss on ignition after drying at 

 ' Alumina . . 



¥)° F. 



Portion soluble in 



Ferric oxide 



Calcium phosphate Large 



hydrochloric acid ■{ Calcium sulphate 



= 87'50. ] Calcium carbonate 



Magnesium carbonate 



1^ Silica 



1 



4'17 

 |- 6-25 

 traces 



t')7-60 

 2-58 

 9-16 



Portion insolublt 



in hydrochloric 



acid = 8-33. 



Insoluble residue, principally alumina and ferric oxide, 



with silica 8'33 



100-00 



A globigerina ooze, containing many pelagic foraminifera of the gen- 

 era Globigerina, Orbuliiia, PulvinuUna, and S]}hoEroidlna ; many coc- 



coliths and rhabdoliths. Ainorplioiis clayey matter with oxide of 



iron. Small particles of sanidine, augite, pumice, magnetite, etc. ; a 

 few grains of manganese peroxide. 



No. 13.— Station XVI. Lat. 20° 39' N., Long. 50° 33' W. Depth, 

 2435 fathoms. Bottom temperature, 1°"7 C. Chemical composition: 



Loss on ignition after drying at 230'' F. 

 ' Alumina 



Portion soluble in 



hydrochloric acid ■{ Calcium sulphate. 



Ferric oxide 



Calcium phosphate Small 



= '78-40. 



Portion insoluble 



in hydrochloric 



acid - 12-00. 



9-60 



4-00 



7-10 



traces 



2-32 



.52-22 



0-76 



12-00 



■ I 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, feldspar, pumice, and horn- 

 blende ; a few grains of manganese peroxide. Many pelagic forami- 

 nifera of the genera Globigerina, Orbulina, Sph(jeroidina^ and Pulvinu- 

 lina ; coccoliths and rhabdoliths. The dredge brought up five small 

 round manganese concretions about the size of marbles, and three 

 shark's teeth of the genus Lamna with a slight coating of manganese 

 peroxide. 



] Calcium carbonate. . . . 



Magnesium carbonate , 

 t Silica 



Alumina 



Ferric oxide 



Lime 



Magnesia 



Silica 



