De Divina Proportione, by Luca Pacioli

This is the Tree of Proportions and Proportionality from the De Divina Proportione of Luca Pacioli, published in 1509.  (Convergence has published Leonardo's woodcuts, taken from this book.)  Some of the terms in Pacioli's tree are familiar today; some are taken originally from the study of proportions by Nicomachus in his Arithmetic; but the meaning of some other terms are not generally known.  It would be a worthwhile project to go through the tree and decipher the meanings of all of the terms in it.