This book does not show of what architecture is composed, but treats of the origin of the building art, how it was fostered, and how it made progress… - Vitruvius

Some people do indeed say that Eratosthenes could not have inferred the true measure of the earth. Whether true or untrue, it cannot affect the truth of what I have written on the fixing of the quarters from which the different winds blow.

Order gives due measure to the members of a work considered separately, and symmetrical agreement to the proportions of the whole. It is an adjustment according to quantity. By this I mean the selection of modules from the members of the work itself and, starting from these individual parts of members, constructing the whole work to correspond.

They make a fine purple colour by treating bilberry in the same way and mixing it with milk.