QUESTIONS TOUCHING MINERALS. 401 



are to enquire of the first stone or ore, or marcasite of 

 metals severally, and what kind of bodies they are, 

 and of the degrees of richness. Also we are to enquire 

 of the means of separating, whether by fire, parting 

 waters, or otherwise. Also for the manner of refin- 

 ing, you are to see how you can multiply the heat, 

 or hasten the opening, and so save the charge in the 

 fining. 



The means of this in three manners ; that is to say, 

 in the blast of the fire ; in the manner of the furnace, 

 to multiply heat by union and reflexion ; and by some 

 additament, or medicines which will help the bodies to 

 open them the sooner. 



Note ; the quickening of the blast, and the multiply- 

 ing of the heat in the furnace, may be the same for all 

 metals ; but the additaments must be several, according 

 to the nature of the metals. Note again, that if you 

 think that [by] the multiplying of the additaments in 

 the same proportion that you multiply the ore, the work 

 will follow, you may be deceived : for quantity in the 

 passive will add more resistance than the same quantity 

 in the active will add force. 



For extracting, you are to enquire what metals con- 

 tain others, and likewise what not ; as lead, silver ; cop- 

 per, silver, &c. 



Note ; although the charge of extraction should ex- 

 ceed the worth, yet that is not the matter. For at least 

 it will discover nature and possibility, the other may be 

 thought on afterwards. 



A\ e are likewise to enquire, what the differences are 

 of those metals which contain more or less other metals, 

 and how that agrees with the poorness or richness of 

 the metals or ore in themselves. As the lead that con- 



VOL. vii. 26 



