“Look At Walls Splashed With A Number Of Stains.....

....or stones of various mixed colours.  If you have to, invent some scene,

 [that] you can see there [that has] resemblances to a number of landscapes

 adorned with mountains, rivers, rocks, trees, great plains, valleys and hills,

 in various ways. Also you can see various battles, and [the] lively postures

 of strange figures, expressions on faces, costumes and an infinite number of things, 

which you can reduce to good integrated form.  This happens on such walls

 and varicoloured stones, [which act] like the sound of bells, in whose peeling

 you can find every name and word that you can imagine."-Leonardo da Vinci