Jusepe de Ribera demonstrating the application of the 14 line armature of the rectangle
The Charles Bouleau Armature vs. The Root Rectangle Armature
In the book “The Painter’s Secret Geometry,” Charles Bouleau talks about the 14 line armature of the rectangle when building a composition in art. Bouleau states that “The lines that cross within a picture, starting from the corners and from the simple divisions of the sides, have been called in this book the ‘armature’ of the geometrical figure formed in and by the picture. The word can suggest any kind of supporting framework, as for instance the leading of stained-glass windows.
But, falling in with the taste of the painters for musical analogies, I am recalling another sense which the word ‘armature’ has in French, that of a key signature—an idea which illuminates what I have in mind by stressing the impersonal, objective necessity of that inner framework which emerges from the form itself and not from the artist’s choice. He may, in accordance with his idea of art, arrange his picture upon the musical consonances or the golden proportion, or inscribe open or closed curves within the area—in all this he is free; the armature, on the contrary, is given him: he will make more or less use of it, but will never be able to do without it entirely.”
He then goes on to say that “To understand clearly what is meant by the armature of the rectangle, it should be noted that the presence of the diagonals does not in every picture leap to the eye. Far from it: it is enough that their points of intersection, or the horizontals or verticals drawn through these to the sides of the picture should supply the construction of the picture with its foundations. When the points have been chosen in this way, the painter withdraws these diagonals, as the builder his scaffolding.”
However, it's important to point out that even though Bouleau’s description of the armature, as discussed in the book The Painter’s Secret Geometry, is constructed differently than the Dynamic Symmetry root rectangles, previously mentioned at the beginning of this user’s guide, both contain the same harmonic divisions.