RESEARCHES ON THE COMPOSITION 
14 
Moisture . 
Bony part. 
q 3 o/ 
Skinny part. 
15.5 % 
Organic matter... 
...43.b ,, 
58.7 „ 
Ash . 
...47.4 „ 
25.8 „ 
Nitrogen . 
....1.88 „ 
8.68 „ 
Phosphoric acid . 
..17.12 „ 
9.52 „ 
Lime. 
..24.54 „ 
14,40 „ 
Magnesia . 
... 1.38 ,. 
0.75 „ 
The composition of the entire shells as calculated from 
these figures, is as follows :— 
Moisture ..10.2 u /o 
Organic matter .45.5 ,, 
Ash .44.3 „ 
Nitrogen . 5.55 ,, 
Phosphoric acid. 16.80 „ 
Lime .21.03 ,, 
Magnesia . 1.29 ,, 
According to these results, turtle shells very much 
resemble the hones of the higher animals ; they are richer 
in nitrogen than the latter, hut the composition of their 
ash is almost identical with that of bone ash. As they can 
be reduced, after a preparatory treatment with steam, and 
with the help of appropriate mills, to a sufficiently fine 
powder, they deserve to be collected and applied as manure 
in the same way as bones. They may probably also serve 
for the manufacture of animal charcoal. 
IV. Various Sea Animals. 
Near the sea a number of marine animals are used as 
manure, especially several kinds of small crabs (kani), 
