Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: June 20, 2025
But when I purposely prepar'd a Menstruum that would dissolve it as Aqua-fortis dissolves Silver, and not barely Corrode it, and quickly let it fall again, I remember not that I took notice of any particular Colour in the Solution, as if the more Whitish Metalls did not much Tinge their Menstruums, though the conspicuously Colour'd Metalls as Gold, and Copper, do.
For we have try'd, that though by Evaporating a Solution of Quick-Silver in Aqua-fortis, and abstracting the Liquor till the remaining matter began to be well, but not too strongly dryed, fair Water pour'd on the remaining Calx made it but somewhat Yellowish; yet when we took good Quick-Silver, and three or four times its weight of Oyl of Vitriol, in case we in a Glass Retort plac'd in Sand drew off the Saline Menstruum from the Metalline Liquor, till there remain'd a dry Calx at the bottome, though this Precipitate were a Snow White Body, yet upon pouring on it a large quantity of fair Water, we did almost in a moment perceive it to pass from a Milky Colour to one of the loveliest Light Yellows that ever we had beheld.
And to part the silver and the gold in the first experiment, they put the mixed body into a glass of aqua-fortis, which separates them by spitting out the silver into such small parts that you cannot tell what it becomes, but turns into the very water and leaves the gold at the bottom clear of itself, with the silver wholly spit out, and yet the gold in the form that it was doubled together in when it was a mixed body of gold and silver, which is a great mystery; and after all this is done to get the silver together out of the water is as strange.
For Lead dissolv'd in Spirit of Vinegar or Aqua-fortis gives a Solution cleer enough, and if the Menstruum be abstracted appears either Diaphanous or White. But here I must take notice, that of all the Metalls, there is not any which doth so easily and constantly disclose its unobvious colour as Copper doth.
This Experiment brings into my mind this other, which oftentimes succceds well enough, though not quite so well as the former; Namely, that if into about a small spoonfull of a Solution of good French Verdigrease made in fair Water, I drop't and shak'd some strong Spirit of Salt, or rather deflegm'd Aqua Fortis, the Greenness of the Solution would be made in a trice almost totally to disappear, & the Liquor held against the Light would scarce seeme other than Cleer or Limpid, to any but an Attentive Eye, which is therefore remarkable; because we know that Aqua-fortis corroding Copper, which is it that gives the Colour to Verdigrease, is wont to reduce it to a Green Blew Solution.
Take of water 1 quart, brazil dust 2 oz., and the size of a nut of alum; boil together, apply while hot and the stain is red; when dry, wash it over with lime water, and it will be a beautiful purple. Take a solution of aqua-fortis in water, apply it to the black, and it will produce a beautiful scarlet. Take of spirits of wine 1 pint, gum benzion half a pound; dissolve the gum in the spirits.
And I have sometimes try'd, that by Rubbing upon a good Touch-stone a certain Metalline mixture so Compounded, that the Impression it left upon the Stone appear'd of a very differing Colour from that of Gold, yet a little of Aqua-fortis would in a Trice make the Golden Colour disclose it self, by Dissolving the other Metalline Corpuscles that conceal'd those of the Gold, which you know that Menstruum will leave Untouch'd.
It must come in thus, "The blots and blurs of our sins must be taken out by the aqua-fortis of our tears; to which aqua-fortis, if you put a fifth part of sal-ammoniac, and set them in a gentle heat, it makes aqua-regia which dissolves gold." And now it is out! Wonderful are the things that are to be done by the help of metaphors and similitudes!
For Gold dissolv'd in Aqua Regia, whether you Precipitate it with Oyl of Tartar which is an Alcaly, or with Spirit of Urine, or Sal Armoniack which belongs to the family of Volatile Salts, will either way afford a Yellow substance: though with such an Acid Liquor, as, I say not Spirit of Salt, the Body that yields it, being upon the matter an Ingredient of Aqua Regis, but Oyl of Vitriol it self, I did not find that I could Precipitate the Metall out of the Solution, or destroy the Colour of it, though the same Oyl of Vitriol would readily Precipitate Silver dissolv'd in Aqua-fortis.
And very merry and good discourse about the business we have been upon, and after dinner went to the Assay Office and there saw the manner of assaying of gold and silver, and how silver melted down with gold do part, just being put into aqua-fortis, the silver turning into water, and the gold lying whole in the very form it was put in, mixed of gold and silver, which is a miracle; and to see no silver at all but turned into water, which they can bring again into itself out of the water.
Word Of The Day
Others Looking