With God´s help I have now discussed in writing, to the extent of my inferior ability, the very necessary practice of tempering color. Now by the bounty of Him who planted understanding in the vitals of mankind I mean to try to relate something of the mixing of colours, for the sake of benevolence and helpfulness to the needy, which one better instructed always shows to other painters.
With pure, that is, with unmixed colours, in order that the painting may be varied, laid in with a mixture underneath shaded above with a colour, cim nimis...