144 Analyses of Booh. [Aug. 



Argentiferous arsenical nickel. 



Arseniferous grey copper ore. 



Antimoniferous grey copper ore. 



Platiniferous grey copper ore. 



Dioptase or copper emerald. 



Native iron. 



Titaniferous oxide of iron. 



White sulphuret of iron. This is the pyrites known 

 in this country by the name of cockscomb pyrites. It lias often 

 a green colour externally, but is always of a very light yellow 

 when broken. It constitutes a distinct species, and probably is 

 composed of different proportions of the constituents from 

 common pyrites. 



Phosphate of iron. 



Arseniate of iron. 



Carbonate of zinc. 



Sulphuret of manganese. 



Ferriferous phosphate of manganese. 



Anatase. 



Oxide of columbium. 



Allanite, or siliciferous oxide of cerium. 



Oxide of chromium. 



III. A great number of additional crystalline forms has been 

 determined by Haiiy, This is the branch of mineralogy in 

 which Hatty's great excellence consists. All his remarks on it 

 are valuable, and entitled to great attention. As he is himself 

 printing at present a second edition of his work, which will 

 make its appearance in a very short time, and as Lucas gives us 

 no figures, and indeed describes no crystals except those noticed 

 by Haiiy in his Tableau Comparatif, it is unnecessary to notice 

 these additions here. The number of forms of calcareous spar 

 made out by Haiiy at present amount to lfcO. The forms of 

 sulphate of barytes are not much fewer. 



IV. M. Lucas terminates his book with a table of die distri- 

 bution of rocks, according to the system of M. Tondi. It is 

 obviously founded upon the geognosy of Werner : from which, 

 indeed, it differs chiefly in the adoption of a great variety of 

 new words to accommodate it to the present French fashion ; 

 and in the introduction of a few rocks not noticed by Werner. I 

 shall endeavour to give the reader an idea of this arrangement. 

 For the term geognosy Tondi substitutes the word oieogrwsy, a 

 faulty appellation, because the object is not to make us ac- 

 quainted with the structure of mountains, but with that of the 

 whole crust of the earth. Oreognosy he divides into three 

 branches ; namely, oreogenesc, or the formation of rocks ; 

 oreotectoniqiie, or the structure of rocks; and oreodiacritique, of 



