i III. DIST. CHAR. Substance. 137 



state, or as they occur in the mineral kingdom. 

 These compounds, in a systematical arrangement, 

 are generally ranked under that division, to which 

 the most essential of the ingredients gives the cha- 

 racteristic property. 



The earths and stones hitherto found under an 

 extraneous form are as follows. 



CALCAREOUS ORDER. 



* Carbonates. 



Chalk. Kirw. p. 77. Form, Animal gene- 

 rally Echinita, more rarely shells or coral. 



Limestone. 

 Compact. 



Common. Kirw. p. 38. F. Animal rarely 

 Veg. 



Roestone. James, p. 480. F. An. sometimes 

 Veg. The smaller grained roestones, as 

 those found in Rutlandshire (at Ketton) 

 Essex, Northamptonshire, &c. frequently 

 contain, and also constitute, the substance 

 of petrifactions. 



Swinestone. Kirw. p. 89. F. An. Fre- 

 quently Belemnittf. 

 Foliated. 



Calcareous spar. Kirw. p. 86. F. An. and 

 Veg. This and the preceding stones form 

 the substance of most animal petrifactions, 

 particularly those belonging to the vermis 

 class. 



