AGLIONBY, William, Painting Illustrated in Three Diallogues. Containing some Choice Observations upon the Art. Together with The Lives of the Most Eminent Painters From Cimabue, to the time of Raphael and Michael Angelo. With an Explanation of the Difficult Terms, London, John Gain, 1685.2 quotations
Is properly any Embossed Sculpture that rises from a flat Superficies. It is said likewise of Painting, that it has a great Relievo, when it is strong, and that the Figures appear round, and as it were, out of the Piece.
Wherein particularly lies the Art of Colouring ?
Beside the Mixture of Colours, such as may answer the Painter’s Aim, it lies in a certain Contention, as I may call it, between the Light and the Shades, which by the means of Colours, are brought to Unite with each other ; and so to give that Roundness to the Figures, which the Italians call Relievo, and for which we have no other Name : In this, if the Shadows are too strong, the Piece is harsh and hard, if too weak, and there be too much Light, ’tis flat.