A Treatise on Painting

The young student should, in the first place, acquire a knowledge of perspective, to enable him to give to every object its proper dimensions: after which, it is requisite that he be under the care of an able master, to accustom him, by degrees, to a good style of drawing the parts. Next, he must study Nature, in order to confirm and fix in his mind the reason of those precepts which he has learnt...