Silver and Copper by reafon of chc shlts itcontzm^ yet ri«c 
touch the Gold s fuch as Verdigrife ^ Lapis Hematites » Crocus 
Martis^ Tutia or calcinated Vitriol With a defcription of the 
Ceinenting Oven , and how it is to be governed i How to Gr^- 
duate Gold and give it an higher colour^" How to niake 
brittle Gold deft and fit to be wrought^ by melting it with 
Nitre and Calx viva^ and other waies. 
Laftly how to caft Gold through Antiiriony ^ which has beeri 
accounted the beft if not the only means to make it very clean 
and fine 5 this the Author allows to be true , when the Anti^ 
mony is good , , but not elfe % and becaufe Jqim l^gis touch- 
^ ethGold only and nor Silver? therefore He judges it may be 
made pureft ajid fined that way. 
The Third Book is altogether of Copper- Oars ^ with their de* 
fcription and the manner of ajfaying theiti^ with many In- 
ilrudtions how to feparate other Metals from them^ but the 
Inftruments and operations being much the fame with what 
went before 5 a more particular account will be but repetiti« 
tion. We fliall only add^ that he gives a fingular way of 
mdtm^ln tht affaymg-lVork^^ and teaches how Copper is- to ba 
made Brafs\ by the addition of Lapis Calamimris ^ by 
which addition the Metal i$ ufually encreafed Sixteen pound 
InaGentner. 
The Fourth Book Treats principally of Lead-Oars^^ni 
briefly likewifeof Tin 3 Antimony ^ Qjiick-filver, Iron ^ Steel 
and the Lost A fione. 
The Brigk^Lead-Oar^^.t fays is the beft, and contains above 
half Lead % befides which there is Wbite-Lead-Oar, like a smid>» 
fione ; and T^ed-Lead-Oar like a reddifh Clay ^ thefe are not 
fo rich as the firft, as neither is ^Tellow-Lead-Oar mixt with 
Cray ^ which is called the Lead-Ram. 
Then follow all the ways of proving it^ as alfo the boyling 
mdfmMngk^ with the cautions to be obfervedin the Beat- 
workj^ &C. In his Chapter of Magnets he quotes a paiTage 
out of Serapim^ how by calcining a Magnet mt\\ an equal 
portion oiCdxviva, and after" adding the Irke weight of yel- 
low sulpJmr^ there will arife a preparation which with the leaft 
Jrop of PFaper ihd 11 imnicdiately take FirA 
C c The 
