In his mixed and violent metaphor, Laxton imagines that money, like the commercial form of nitric acid, aquafortis, will consume and vanquish a maidenhead.
If metaphors require difference, this one seems to collapse into itself, because the aquafortis whose function is supposed to be figurative in his formulation also has a literal meaning in relation to money; it was used to produce counterfeit coins.
Coins could also be placed together in a bag and shaken vigorously to produce metal dust, a process that was called "sweating"; or they could be "washed," a process that used acid, perhaps aquafortis, to remove some of the precious metal without altering the image on the coin.
Money is like aquafortis, and the monetary system produces anxieties similar to forms of counterfeit in which the outward appearance does not resemble the inner content.
Blake, after deeply perplexing himself as to the mode of accomplishing the publication of his illustrated songs without their being subject to the expense of letter press, his brother Robert stood before him in one of his visionary imaginations, and so decidedly directed him in the way in which he ought to proceed, that he immediately followed his advice, by writing his poetry and drawing his marginal subjects of embellishments in outline upon the copper-plate with an impervious liquid, and then eating the plain parts or lights away with aquafortis
considerably below them, so that the outlines were left as a stereotype.