J. Lawrence Smith on Meteorites. 323 
and ‘chrome iron affording in their crystalline form angles identical 
with those of terrestrial origin. 
t perhaps of all the interesting facts under this head developed 
by meteorites, is the universality of the laws of chemical affinity, 
or the truth, that all the laws of chemical combination and atomic 
Constitution are to be equally well seen in extra-terestrial and 
terrestrial matter; so that were Dalton or Berzelius to seek for the 
atomic weights of iron, silica or magnesia they might learn them 
as well from meteoric minerals as from those taken from the bowels 
of the earth. The atomic constitution of meteoric anorthite or of 
pyroxene is the same as that which exists in our own rocks. 
eeping in view then the physical and chemical characters of 
meteorites, I propose to offer some theoretical considerations 
Which to be fully appreciated must be followed step by step. 
These views are not offered, because they individually possess 
particular novelty ; it is the manner in which they are combined, 
to which especial attention is called. 
Physical Characteristics to be noted in Meteorites.—The first 
physical characteristic to be noted is their form. No masses of rock, 
however rudely detached from a quarry, or blasted from the side 
of a mountain, or ejected from the mouth of a volcano, would 
present more diversity of form than meteoric stones: they are 
rounded, cubical, oblong, jagged, flattened, and in fine they pre- 
Sent a great variety of fantastic shapes. Now the fact of form 
I conceive to be a most important point for consideration in re- 
gard to the origin of these bodies; as the form alone is strong 
proof that the individual meteorites have not always been cos- 
I pass to another point—namely the crystalline structure ; more 
especially that of the iron, and the complete separation in nod- 
Metal, combining only with a limited portion to form particular 
Minerals ; and did we aim to imitate such separation by artificial 
Processes, we could only hope to do it by retaining the iron ina 
Plastic condition for a great length of time. Also, no other agent 
than fire can be conceived of by which this metal could be kept 
in the condition requisite for the separation. _ 
If these ae ah, reference to the crystalline structure be ad- 
Mitted, the natural suggestion is that they could only have been 
thus heated while a part of some large body, 
