Of the P V R I T E S. ££ 



originally created; as all fuch ftones and earths? 

 confiiting of fand, of calcarious and flimy matters* 

 the reliques of the flood, becoming afterwards 

 hardened, were without copper-ore. And thus, 

 propoficions abfolutely general, are noteafily to be 

 admitted into the fcience of nature : as we cannot 

 well conclude, that becaufe a thing has not been 

 hitherto fo obferved, it neither is, nor can be fo. 

 That a thing exifts, and in fuch and fuch circum- 

 ftances, we may afluredly affirm, but that it can- 

 not be in any other than thefe, would be indifcre- 

 tion to affert. And with this I might juftly 

 charge myfelf, fhould I, from copper-ore not be- 

 ing hitherto found in lime-ftone, thence form a 

 general conclufion. In the mine-hiftory we have 

 many very curious remarks, deduced from much 

 and long experience : for inflance, that fuch and 

 fuch circumilances, and the appearance of fuch 

 and fuch minerals, give hopes of fome ore or 

 other , but it might tend to great miftakes, to 

 form unlimited, abfolute propofitions from fuch 

 remarks : for, often, the ores prefumed, either 

 appear not at all, or very different from what was 

 expected. From the nature of the upper-garden, 

 or under-turf mould, we attempt to form a judge- 

 ment of the fubjacent mould, of the prefence or 

 abfence of any ore, and of this or that particular 

 fort of ore ; as if the lower contents were necefTa- 

 rily derived from the upper : we are, therefore, 

 carefully to avoid being too precipitate in forming 

 axioms and conclufions. Our bufinefs, firft, of all, 

 is to make obfervations, proper remarks, and col-» 

 leer, inflance s together, without pretending to de- 

 duce any confequences : for how fuperficial often 

 are even the moil accurate remarks and obferva- 

 tions ! Our experience is chance- work ; our ar- 

 dent purfuit after riches fo much engrofles our 

 thoughts^ as to make tiat our only end in the 



E 4 bu- 



