"The following pages describe the section of De Divina Proportione which comprises diagrams of the true shapes and proportions of classical Roman letters, and provides some discussion of lettering in the interests of such contemporaries of his [Luca's] as were architects in his native city of Borgo San Sepolcro. This discussion, although not the earliest, forms the first serious treatise of this kind to be printed and became the inspiration of the successive similar works by Albrecht Dürer and by Geoffroy Tory."