On tempering gold. Take ochre, and temper it with water, and so set it aside to dry. Meanwhile, make a glue from calf-skin parchment; then prepare the white of an egg, and mix the glue and the white of egg together, and when the ochre is thoroughly dry, grind it well on the marble. And wherever you wish to lay gold on the parchment, spread the ochre on the parchment with a brush as soon as it is ground. And then you may lay the gold upon it, and put it aside to dry, without pressing it with the cotton. And then burnish it well with a tooth.