What is a kind of etching in which spaces are bitten by the use of aqua fortis, by which an effect is produced resembling a drawing in water colors or India ink; also, the engraving produced by this method called?

aquatinta — A kind of etching in which spaces are bitten by the use of aqua fortis, by which an effect is produced resembling a drawing in water colors or India ink; also, the engraving produced by this method. (Webster's 1913.)

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