Mineralogy, according to the Principles of Professor MOHS. 301 



" quantity, and mode of combination of the constituent parts." 

 This is in fact tacitly supposing the results of mineralogy and 

 chemistry already to have been brought to a degree of coinci- 

 dence, which, though it may be rightly anticipated, has yet not 

 been established, even by the recent most rapid progress of the 

 two sciences. In this way the determination of the species of 

 WERNER, was almost entirely left to a certain tact which admits 

 of no definition, and must be more admired in the correct results 

 occasionally obtained, than praised for the certainty with which 

 the method could be pursued. 



The definition of the species, as given by HAUY, that it com- 

 prises bodies having similar integral molecules, and being composed 

 of the same elements, in the same proportion *, consists of two he- 

 terogeneous parts, the first of which, taken alone, is insufficient, 

 though appertaining to the science, while the second is altoge- 

 ther foreign to mineralogy. 



Natural Philosophy has been defined as " the science that 

 " unfolds those general principles which connect the events of 

 " the material world f ." As a branch of natural philosophy, 

 the science of Chemistry regards the events produced by the ac- 

 tion of bodies upon each other, in which the changes produced 

 are permanent, and, therefore, like the whole of natural philoso- 

 phy, it investigates phenomena in reference to their causes. 



It is necessary to know what things those are, which act upon 

 one another; and definitions must therefore precede, before it is 

 possible to enter into the details of these sciences themselves. 

 One word may very often suffice for the definition of one object, 

 but if there be a great many, some of them, too, possessing very 

 similar properties, a degree of order must be introduced, even 

 in the enumeration of the above-mentioned definitions. 



- j - * t . ' * ; 1 1 : . . . 



* Traitt, t. i. p. 162. 



+ LESLIE, Elements of Natural Philosophy, p. 1. 



