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the quantity of silicium present, shows the mixture to consist of 48*5 per 
cent, of pig iron and 51*5 per cent, of a phosphide composed of 
Iron ....... 88"05 
Phosphorus 11'95 
100-00 
A second similar experiment, made six months later, gave numbers which 
point to the fusible phosphide having the composition 
Iron ....... 88*26 
Phosphorus 1P74 
100-00 
It appears, therefore, to possess a definite composition corresponding to 
the formula Pe 4 P. 
Nodules from the Beep Sea . — Giimbel publishes an interesting and very 
complete analysis of some of these nodules. Between Japan and the Sand- 
wich Islands the sea-bed is covered with red mud, fragments of pumice, and 
the so-called u Manganese ^nodules.” Those which he examined had been 
dredged up by the “ Challenger ” from a depth of 2,740 fathoms. They are 
rounded or flattened, have a dull brown colour, and enclose particles of 
pumice, teeth of fish, &c. The nodules scale off in layers, and a careful 
inspection of cross sections convinced the author that the structure is due to 
mechanical action, and not to the agency of any organism. The pumice is 
trachytic. He is of opinion that the material constituting the nodules has 
been derived from submarine sources. A very complete analysis of a frag- 
ment of one of these interesting bodies was made, and it was found to have 
the following composition : 
Iron sesquioxide 
. 27-460 
Manganese peroxide . 
. 23-600 
Alumina .... 
. 10-210 
Lime .... 
0-920 
Magnesia .... 
0181 
Soda .... 
2-358 
Potash .... 
0-396 
Baryta .... 
0-069 
Silicic acid 
. 16-030 
Titanic acid 
0-660 
Sulphuric acid . 
0-484 
Carbonic acid . 
0-047 
Phosphoric acid 
0023 
Chlorine .... 
0-941 
Copper oxide 
0-023 
Nickel (cobalt) oxide 
0012 
Water .... 
. 17-819 
101-233 
The low proportion of carbonic acid present in these nodules is very 
remarkable ( Sitzungs-Ber . baeyer. Akad. TViss. 1878, 2.) 
