Notices respecting Neit) Books. 557 



acted with good faith towards M. Heuland, have been long since 

 published. It is however stated, that after receiving a large sum of 

 money during the progress of the work, that M. L^vy " promettait 

 bien de terminer les planches, mais il promettait toujours, et n'ache- 

 vait rien." It is afterwards even stated that for the completion of 

 the work M. Heuland lies under obligation to the friendship of Mr. 

 J. H. Brooke and his son, and other gentlemen whom he names. 



The delay has, however, very little, if at all, impaired the useful- 

 ness of the work to the mineralogist, in reference to their geogra- 

 phical relations, and the great variety of their crystals. 



It is difficult to select, but we would direct the reader's attention 

 particularly to the extensive series of forms of carbonate of lime, sul- 

 phate of barytes, topaz, epidote, pyroxene, and idocrase ; and among 

 the metals red silver, blue carbonate of copper, and other of the less 

 common substances ; and indeed, we cannot but express our sur- 

 prise that so large a collection, containing so great and such a 

 splendid variety of crystals, should be found in any single cabinet ; 

 and if it were not for the full, and, we conclude, accurate descriptions 

 of the specimens given in the work, we should greatly regret that 

 they were rendered less acceptable than the cultivator of mineralogy 

 would desire, by the distance of Mr. Turner's residence from 

 London. 



To give some idea of the extent of the collection, we may remark, 

 that of carbonate of lime, the substance first mentioned, 513 varieties 

 are described ; the crystalline forms of it occupy ten plates ; these 

 require 158 figures, which are drawn and engraved with great clear- 

 ness and precision : besides these, the crystalline forms of arragonite 

 and magnesian limestone occupy two plates. The analyses and che- 

 mical formulae of each substance are included in its description, and 

 we do not think that we can give a better idea of the manner in which 

 the work is conducted than by copying a portion of it which relates to 

 red silver, of which 55 varieties and 106 specimens are described, with 

 engravings of 39 crystals. 



The first 14 varieties, all we think it requisite to give, are thus de- 

 scribed ; 



*' ARGENT ROUGE. 



** Caracteres d^finis. 



Thenard. Formule chimique. 



" Analyse. Argent 58. 2 A « S^ + 3 A^f S«. 



Antimoine. . 23,5. 



Soufre , ... 16. 



Perte 2,5. 



100,0. 

 *' Forme primitive. Rhomboide obtus de 108° 30'. 

 " Clivage. Parall^le aux faces du rhomboide primitif. 

 " Pesanteur sp^cifique. 5,5886... 5,846. Cristaux de Beschert- 

 gluck. 



" Caracteres indejinis. 

 ** Chimiques, Au chalumeau, dccrepite en repandant une odeur 



