94 



MINERAL GALLEKY. 



Larger 



Mineral 



Specimens. 



depending on the amount of change which has taken place, 

 and thus being less definite than in the preceding minerals. 

 In the variety called Anthracite all traces of the original 



Amber. organised structure have disappeared. Amber (41c), in ancient 



times regarded as one of the precious stones, is likewise 

 of vegetable origin. It is a fossil resin, chiefly derived 

 from trees allied to the pines ; its originally sticky con- 

 dition is sufficiently proved by the insects sometimes found 

 enclosed. 



In the gallery and pavilion at the east end the visitor will 

 find many specimens which, owing to their size, cannot be 

 satisfactorily exhibited in the table-cases. 



Among these, attention may be directed to the magnificent 

 series of minerals in the wall-cases, and to the specimens of 

 Galena and Jade on separate tables; as well as to the large 

 specimen of Gypsum, or Selenite, presented by the late Prince 

 Consort, which, with some fine illustrations of Calcite, is ex- 

 hibited in a special case. 



Of the four table-cases in the windows of the pavilion, the 

 first three contain a series illustrating the various kinds of 

 Pseudomorphs, or minerals in which the original constituent 

 has been dissolved away and replaced by a new substance 

 which preserves the crystalline form of the first. The fourth 

 displays a set of specimens selected by Professor Euskin to 

 illustrate varieties of Silica. 



Meteorites. The most important feature of the pavilion is the collection 



of Meteorites,* of which the smaller specimens are shown in the 

 four central cases. The fall of masses of stone and iron from 

 the sky, though observed again and again since the most remote 

 ages, was very rarely credited by anyone beside the spectators 

 themselves ; and tiU the beginning of the eighteenth century no 

 attempt to collect such specimens for examination and comparison 

 was made. In the special guide it is shown how evidence of the 

 actual fall of such bodies at length became irresistible, and a 

 description is given of the circumstances attending their fall, 

 of their general characters, and their chemical composition : 

 illustrative specimens, collected together for easy reference, wiU 



* See "An Introduction to the Study of Meteorites, with a List of the 

 Meteorites represented in the CoUeptioj)." Pj-ipe sj?pgace. 



