124 MUSEUM METEORITES—HONEYMAN. 
in their orbits) Whatever may be the region whence these 
masses proceed, they constitute the only tangible products which 
reach us of celestial bodies. Anyone can comprehend the interest 
that their study presents, not only for Astronomy, but also for 
Geology, who thus sees the horizons of these to be enlarged, and 
who draws a comparison between these bodies from a distance 
with our globe of ‘useful information’ (d’utiles renseignements) 
on the mode of the formation of the latter and of our planetary 
system, as I shall try to demonstrate. 
It seems to me that the time has arrived for confirming by 
synthetic experiments the numerous notions, that analysis has 
furnished, on the constitution of meteorites. 
Permit me to hope that experimental synthesis will not render 
less service in this study than in that of the earth’s rocks and 
minerals. 
Before entering on this subject I would state very briefly— 
That the various Meteorites known arrange themselves into 
two grand divisions: the irons (jers) and the stones (pierres) 
The Irons : 
I. Of the first we have established three divisions. 
1. Iron with a mixture of stony matter (Meteorite of Caille, 
Var.) 
2. Iron containing globules of peridote (Fer de Pallas.) 
3. Iron associated with the Silicates peridote (olivine) and 
pyroxene (augite), (Sierra de Chaco.) 
The last establishes a connection between the two grand 
divisions established, between the extremes—in appearance so 
different. 
II. The stones, for the most part, do not contain native iron 
except in small grains, and disseminated in the Silicates princi- 
pally with a base of magnesia and of protoxide of iron, of which 
the peridote forms in general a great part. It is this group that 
we designate here, by reason of its extreme frequence, under the 
name of the “common type.” ° 
The other stony Meteorites which do not contain native iron 
can be referred to three principal groups :— 
Ist. In the one, the magnesian silicates predominate, On the 
