Page:Theophrastus - History of Stones - Hill (1774).djvu/239

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C. ^[1]People who prepare Colours ſay alſo, that the Lapis Armenus of itſelf makes four different ones; the two extremes of which are, firſt, that which conſiſts only of its fineſt Particles, and is very pale; and the other, that which conſiſts of its largeſt, and is extremely deep.

CI. But theſe are the Works of Art, as is alſo Ceruſe^[2], to make which, Lead

gyptii aſcribitur, qui primus eam tinxit; dividitur autem & hæc in mares fæminaſques ineſt ei aliquando & aureus pulvis, &c.

↑ The Colours, of different Degrees of Deepneſs, which were prepared from this Subſtance, were ſeparated by means of Water: The Method of preparing them was, by beating the Matter to Powder, and putting that in a large Quantity of Water, and ſaving, in different Veſſels, that which ſubſided at different Times: the heavier Part, conſiſting of larger Particles, ſinking almoſt immediately, and the lighter, which conſiſted of much ſmaller and finer, not till after a conſiderable Time. Theſe different Quantities of Colour, that had ſubſided at the various Times, were then ſeparately ground to a proper Fineneſs, and kept as different Paints for Uſe. And this is the Meaning of the λεπτοτάτων and παχυτάτων of our Author, and Craſſiorem tenuioremve of Pliny: Which ſome, who imagined they were talking of the Degree of Colour, and not of the Fineneſs and Coarſeneſs of the Particles of the Matter, could not bring themſelves to underſtand. Indeed, in many of the Paſſages complained of as unintelligible in the Antients, the Obſcurity has been more owing to the wrong Apprehenſion of the Commentators, than the Perplexity of the Authors.
↑ We have three or four different Methods of making Ceruſe now uſed among us; but all are of the ſame Kind with this of Theophraſtus, and are the Effect of Vinegar on Lead. It is by ſome made by infuſing Filings of Lead in ſtrong Vinegar; which in twelve or fourteen Days will almoſt entirely diſſolve them, and leave a very good Ceruſe at the Bottom of the Veſſel. Others make it, by plunging thin Plates of the ſame Metal into Vinegar, and placing them. in a gentle Heat; theſe

[2] The Colours, of different Degrees of Deepneſs, which were prepared from this Subſtance, were ſeparated by means of Water: The Method of preparing them was, by beating the Matter to Powder, and putting that in a large Quantity of Water, and ſaving, in different Veſſels, that which ſubſided at different Times: the heavier Part, conſiſting of larger Particles, ſinking almoſt immediately, and the lighter, which conſiſted of much ſmaller and finer, not till after a conſiderable Time. Theſe different Quantities of Colour, that had ſubſided at the various Times, were then ſeparately ground to a proper Fineneſs, and kept as different Paints for Uſe. And this is the Meaning of the λεπτοτάτων and παχυτάτων of our Author, and Craſſiorem tenuioremve of Pliny: Which ſome, who imagined they were talking of the Degree of Colour, and not of the Fineneſs and Coarſeneſs of the Particles of the Matter, could not bring themſelves to underſtand. Indeed, in many of the Paſſages complained of as unintelligible in the Antients, the Obſcurity has been more owing to the wrong Apprehenſion of the Commentators, than the Perplexity of the Authors.

[p223-3] We have three or four different Methods of making Ceruſe now uſed among us; but all are of the ſame Kind with this of Theophraſtus, and are the Effect of Vinegar on Lead. It is by ſome made by infuſing Filings of Lead in ſtrong Vinegar; which in twelve or fourteen Days will almoſt entirely diſſolve them, and leave a very good Ceruſe at the Bottom of the Veſſel. Others make it, by plunging thin Plates of the ſame Metal into Vinegar, and placing them. in a gentle Heat; theſe

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