36 



when truncated at the edges, as they are in the specimen 

 spoken of — see the right hand outline. 



It is a curious lesson in the study of Chemistry to search 

 for the menstruum in which the Sulphate of Barytes may 

 be dissolved without hurting the Carbonate of Lime ; for it is 

 too much undercut, as the workmen would say, to deliver 

 the cast whole ; and the facets of the Barytes are very sharp 

 in the mould, and indicate some rare ones that appear to 

 have been extremely smooth with bright and polished sur- 

 faces. Whether the Ochre, or other pulverulent matter 

 which is about the specimen, helped it to separate, I dare 

 not say ; but I scarcely think that would have been suffi- 

 cient of itself. 



