CENTURY OF STUDY OF METEORITES. 197 



1)0 flono, many theories rogardino- the nature and origin of nieteorvte.s 

 which have ))een found untenal)le as a result of the contur^-'s study. 

 The theory of the hinar orig-in of meteorites had at times such able 

 supporters as Laplace and J. Lawrence Smith. Other a})le observers 

 have believed meteorites to be material ejected at some past period 

 from the earth's volcanoes, some have regarded them of solar origin, 

 and still others as fragments of a shattered planet. All of these 

 theories may be said to have been proved fallacious. The discover}^ 

 reported by Hahn in ISSO of remains of sponges, corals, and plants in 

 meteorites excited for a time eag"er iiKjuiries into the possibilities of 

 proving by the stud}^ of meteorites the existence of life outside our 

 own globe. No satisfactory evidence of the existence of extraterres- 

 trial life has. however, as vet been obtained from meteorites. The 

 most positive and enduring results of the century's study ma}', there- 

 fore, perhaps be summed up as the establishment of the fact of the 

 fall of solid cosmic matter to the earth and a sufficient knowledge of 

 its nature to distinguish it from matter of terrestrial origin. Satis- 

 factory conclusions as to the origin of this matter and its relations to 

 the visilile bodies of the great outl3dng universe remain yet to be 

 drawn. 



