1905.] NATURAL SCIENCES OF PHILADELPHIA. 913 



dissipated in the smaller meteorites and that they strike the earth with 

 a very moderate velocity ; but could such a thin layer as the atmosphere 

 deal in the same manner with a large body? The author is of the 

 opinion that it could not, and that this body probably struck with a 

 large part of its planetary velocity, and that it was extremely small in 

 comparison with anything that would be deduced by assuming for it 

 any such striking velocity as has ever been produced in a terrestrial 

 projectile; but as and for the reason set forth above, he does not feel 

 justified from any known data in naming any definite figure in con- 

 nection therewith. 



The Composition of the Meteorite. 



The composition of the outer surface, at least, of this meteorite is 

 fairly well known and appears to have been fairly constant. For the 

 great numbers of specimens picked up around the hole, which must 

 have come indiscriminately from all points of the surface, are of fairly 

 constant composition. That is, metallic iron with very small percent- 

 ages of carbon, sulphur and phosphorus, with between seven and eight 

 per cent, of nickel and a trace of cobalt. This metallic mass carries 

 about three-fourths of an ounce per ton of platinum and iridium. 



As to the interior composition of the meteorite, nothing definite can 

 be known. If the body was a fragment the probability is that it was 

 homogeneous throughout, as there is little or no difference between 

 the fragments from all portions of its surface. If, however, the object 

 was a small spheroid its interior might differ considerably from that of 

 its exterior. It seems improbable that the mass contained any notable 

 proportion of stony material, as nothing of this kind has been observed 

 in the fragments around the rim, nor has prolonged and careful micro- 

 scopic examination of a very large number of samples of the filling 

 material of the hole from all depths shown anything but the broken 

 debris of the strata penetrated, except the above-mentioned meteoric 

 material, which is all either metallic iron or the direct results of its 

 combustion or union of such products of combustion with the surround- 

 ing silica. It is, however, to be noted that a small stone meteorite of 

 several pounds in weight, containing metallic iron sparsely scattered 

 through it, was picked up by i\Ir. Barringer about two miles from the 

 crater. There is, however, excellent reason for the belief that this 

 object was observed to fall during the winter of 1903. In any event, 

 although the iron contains a proportion of nickel somewhat less than 

 that in the fragments of the great meteorite, yet, after careful and 

 repeated examinations, it has been proved that the metals of the plati- 

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