I INTRODUCTION. 



guages, the names are almost always general, that is to say, 

 vague expressions for objects of the same similitude, however 

 distinct. An oak, a beech, a linden, a yew, a pine, a fir, 

 will all at first be called a tree; then the oak, the beech, the 

 linden, will all be called oaks, till they be distinguished from 

 the others, which will be called pines. But particular names 

 will only be found in an advanced state of society, after com- 

 parisons and examinations j and the number has been always 

 increased in proportion as nature is more studied and better 

 known; and the more it is examined and compared, the 

 more abundant will be the proper names and peculiar deno- 

 minations. But when we are now presented with general 

 terms, that is genera, it is to send us back to the A B C of 

 knowledge, and recall the darkness of the infancy of nations. 

 Ignorance has created genera, science has produced, and 

 always will produce, proper names -, and we are never afraid 

 to augment the number of particular denominations when 

 we wish to designate different objects." 



This eloquent author was, however, too inimical to systems 

 of nomenclature on the Linnaean plgn; and his observations 

 may be considered as chiefly applicable to mineralogy, in 

 which the arbitrary divisions have been so often confounded, 

 as has already been explained in the general introduction to 

 this work. The most severely scientific writer on mineralogy 



Hauy's j Haiiy, but even he has been obliged repeatedly to chang-e 

 deviations. . Al _ 



the subdivisions 5 for in the nrst class he has genera, in the 



second only species j in the third there are two orders ; in 

 the fourth three orders, and every metal forms a genus. Nay, 

 as already stated, he has changed the very foundation of his 

 plan, having formally abandoned the integrant molecule, 

 which, as he supposed, constituted the species, for the primi- 

 tive form, as he confesses that he was often deceived by the 

 integrant molecule*. This molecule was the invention of 



* His argument that crystals resemble the flowers of plants, as a criterion of 

 species, is not just, the crystals being often different from the substance, quartz 

 in limestone, barytes in granite, &c. &c. 



