II PREFACE. 



were sent over during the progress of publication. 

 In consequence of a continued correspondence with 

 Professor MOHS, and the present rapid progress of 

 the science itself, the translator found it necessary 

 to make many alterations, improvements, and addi- 

 tions ; so that this Treatise on Mineralogy may be 

 considered in many respects as a second edition, 

 rather than as a mere translation of the original 

 work. 



The principles according to which Mineralogy is 

 here treated, are so different from those generally 

 received, that, in order to prepare the public for 

 the reception of his method, the author found it ne- 

 cessary to give a full developement of his ideas in 

 a Preface of considerable length ; and this was the 

 more indispensable, as the second volume was not 

 published along with the first. In conformity with 

 the views of Mr MOHS, the translator has endea- 

 voured to attain the same object, by publishing 

 in the Transactions of the Royal Society of Edin- 

 burgh, and in the scientific journals of that city, 

 several papers drawn up in strict accordance with 

 these principles, and shewing their application in 

 particular cases. These papers were designed to con- 

 vey a just idea of the leading principles of the pre- 

 sent work, from which even the substance of some 

 of them is extracted. From these considerations, it 

 would be superfluous to give here the translation 

 of that part of the German Preface which regards 



