OF ARTS AND SCIENCES. 39 



The alphabetical index appended to this catalogue includes all the 

 names by which the meteorites are commonly known, and refers both 

 to the page and catalogue number. 



Figures illustrating some of the most striking examples of crystalline 

 structure have been grouped in five plates, and are referred to in the 

 catalogue by numbers. On the plates, in connection with the number 

 of the figure, is also given the number of the page on which the speci- 

 men is described. 



Although great care has been taken in the preparation of the cata- 

 logue, and many of the mistakes of previous catalogues have been 

 corrected, yet the writer fears that many of the data which have been 

 accepted on the best authority may be erroneous, and that this cata- 

 logue is by no means perfect. Even in regard to the circumstances 

 of an observed fall, entire reliance can seldom be placed on the testi- 

 mony of the original observers, who are often untrained, and over- 

 powered by the startling phenomena ; and there is frequently the 

 difficulty of reconciling conflicting testimony. The connection between 

 the fire-ball which attracted attention and the meteorite subsequently 

 found is often only assumed, and not established. 



The facts connected with the discovery of a meteorite are often 

 more difficult to determine than those of an authentic fall. The only 

 date which should be recognized is that of the publication in which 

 the meteoric origin of the mass is first recognized ; but after this is 

 made known, it often appears that the specimen had been seen several 

 years previously, and the discovery has been frequently antedated on 

 the ground of such uncertain evidence. Again, it is often difficult to 

 decide, especially in the case of meteoric irons, whether they really 

 represent distinct falls. In some cases, pieces obviously of the same 

 fall have become scattered over quite wide geographical areas, either 

 as the result of successive explosions during the original flight of the 

 meteorite, or else because distributed by human agency on account of 

 some supposed value or sacred association. Moreover, the artificial 

 value which rare meteoric specimens have acquired naturally inclines 

 collectors to regard each new find as a distinct fall, and to enhance the 

 value of the specimen by keeping it undivided. Such, and many other 

 questions, which could not be settled with the limited means afforded 

 even by so large a collection as that of Harvard College, have arisen 

 in the preparation of this catalogue. Still, it is hoped that the work 

 may be found of value in verifying and extending the history of these 

 remarkable bodies. 



