VICTORIAN METEORITES, WITH NOTES ON OBSIDIANITES. 
It seems to be quite as dense as the other iron until treated with 
hydrochloric acid, when porosity is produced, and the specimens 
acquire the appearance of being traversed by a series of very fine 
cracks. The structure must, consequently, be due to the removal 
of some easily-soluble constituent, probablv troilite. The com- 
position of the iron does not differ materially from that of the mass. 
The analysis of the Beaconsfield material is given here for comparison. 
If, as Cohen suggests, the iron consists of a mixture of taenite 
and kamacite plates, the residual portion should, on account of its 
greater insolubility, be composed for the most part of taenite. The 
Beaconsfield analysis shows the nickel contents to be slightly under 
7 per cent., while the taenite of that meteorite yielded the very 
high result of about 48 per cent. It is, therefore, fairly obvious 
that the solvent action of dilute hydrochloric acid would have the 
effect of increasing the nickel contents by dissolving out the kamacite. 
The residual product would vary in its percentage of nickel according 
to the amount of solvent action, from something considerably higher 
than that of kamacite up to that of almost pure taenite. On the 
contrary, Cohen’s figures show a lower amount of nickel than the 
bulk. 
A white nickel-iron, looking like taenite, forms a fine clearly 
defined and uniform margin to part of the branching schreibersite 
surrounding a troilite nodule, and also to another nodule in which 
schreibersite is absent. 
At a certain incidence of light it contrasts strongly with 
the granular silvery-white schreibersite on the one _ side, and 
the grey nickel-iron forming the mass of the meteorite on the 
other. 
Troilite. — On the polished face of the meteorite, measuring 
about 12 cm. by 9 cm., there are sections of five nodules. Three of 
them are of regular oval form. The largest occurs on the edge of 
the face, and only about half of it has been cut through. I* measures 
about 30 mm. in length, by about 20 mm. in breadth. These 
three nodules consist of troilite surrounded more or less completely, 
felt by a regular shell of graphite, and then by schreibersite. The 
remaining two nodules are of a more irregular shape and more 
circular than oval. In one the troilite is mixed with the graphite 
urn the other srapliite replaces troilite as a nucleus, the latter 
SwtrU - irregular 1 and broken e^og. ^e trodite 
riso seems to occur as an impregnation of the graphite nodules. 
The face of the piece cut from the meteorite shows only one nodule 
of very perfect oval form, 8 mm. by 5 mm in which very small 
fragmentary pieces of troilite occur in the schreibersite outside the 
graphite envelope. 
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