EEPORT ON THE DEEP-SEA DEPOSITS. 
489 
139 and 140. Carcharodon Tooth. — Station 285. Lat. 32° 36' S., long. 137° 43' W., 2375 fathoms (Dittmar). 
The tooth weighed 22 grms. The outer shell was readily detached from the inner portion. 
139. The outside portion was found to contain 33'66 per cent, of phosphoric acid, equal to 73'48 per cent, 
of tricalcic phosphate, and 2'28 per cent, of fluorine. Ratio of equivalents of phosphoric acid to fluorine — 
1 : 0-1 
140. The inside portion was completely analysed, with the following results : — 
P. 
Silica and portion insoluble in hydrochloric acid, . . . 13 ’34 
Moisture, . . . . . . . . 8'41 
Combined water, . . . . . . . 6 '93 
Manganous oxide (MnO),^ . . . . . . 35'51 
Loose oxygen, 1 ........ 6'85 
Ferric oxide,^ ........ 12'47 
Alumina, . . . . . . . . 5‘09 
Lime, . . . . . . . . . 3'72 
Magnesia, . . . . . . . . 3'74 
Potash, . . . . . . . . . 0'56 
Soda, . . . . , . . . 1 '31 
Phosphoric acid, . . . . . . . 0'83 
Carbonic acid, . . . . . . . . 1'19 
Silica in solution, . . . . . . . 0 ’30 
Chlorine and copper, ....... traces 
E. 
V. 
E. 
35-5 = 1 
8 =0-8562 
80 =0-1556 
100-25 
^ The extra oxygen in the ferric oxide, as the quotients show, is more than sufficient to convert the manganous oxide into 
binoxide. 
141 and 142. Oxyrhina Teeth.— Station 286. Lat. 33° 29' S., long. 133° 22' W., 2335 fathoms (Dittmar). 
Colour, brownish black. 
The teeth consisted of a tough outer shell filled up with a friable black mass. 
Three of the teeth were taken, the inside portion separated from the shell, and the percentages of phosphoric 
acid determined, with the following results : — 
(141) (142) 
Inside. Outside. 
Per cent, of phosphoric acid, . . . . .7-97 32-58 
Equal to tricalcic phosphate, . . . . .17-39 71-12 
143. Earbonb. — Station 285. Lat. 32° 36' S., long. 137° 43' W., 2375 fathoms (Brazier). 
Portion 
Portion 
soluble in Hydrochloric 
Acid = 95 -04 
insoluble in Hydrochloric 
Acid = 0-36 
} 
Loss on ignition after drying at 230° Fahr. , 
4-60 
Alumina, 
0-50 
Ferric oxide. 
9-28 
Calcium phosphate. 
. 67-72 
Manganese oxide, . 
2-85 
Calcium sulphate, . 
2-69 
Calcium carbonate, . 
. 10-95 
Magnesium carbonate. 
0-75 
, Silica, 
0-30 
Insoluble residue, . 
0-36 
I 
100-00 
Note. — Portion of earbone; total weight 244 gi-ains. Beside the details given in the foregoing analysis, it evidently con- 
tained nitrogenous organic matter in small quantity. By comparative experiments it was found to contain more than the 
piece of bone used in Analysis 149, and about the same as the shark’s tooth used in Analysis 137. From material left over 
from this specimen and the tooth of Analysis 137, a nitrogen determination was made and yielded 0-052 per cent, of nitrogen. 
(deep-sea deposits chall. exp. — 1891.) 64 
