The Recognitions - pg. 874

- You'll say I should have microscopes for this ... delicate work. Yes, egg white, egg yolk, gums, resins, oils, glue, mordants, varnish, you'll be surprised how they're put together just to bind the pigments. We could take X-ray pictures, infra-red, ultra-violet ... Layers and layers of colors and oils and varnish, and the dirt! The dirt! Look at that, that picture there, look at the crackle on the surface, that's from the wood panel expanding and contracting and the paint crackles when it gets dry. If we had a microscope with a Leitz mirror-condenser, we could turn it up to five hundred diameters, put on a counting disc and make a particle count of the pigment. Then we measure its thickness with a micrometer, put the Micro-Ibso attachment on the camera and you ... If we had a micro-extraction apparatus we could bore holes in it too and get some nice cross sections out, put them in wax and then you slice them in half just like that with a microtome knife. And when you get that under a microscope with polarized incident light then you can really see what's going on with a carbon arc lamp, you'll see when we get into the high oil immersion series of lenses. You'll see, if we can fix a microscope up with polarized light and put a particle of the pigment under it, we can see whether it's isotropic or anisotropic, for that we use nicol prisms. Then we determine the refraction index of the particles of pigment and then, well then of course, then we know exactly ... the dirt that collects in every little ridge and crack century after century, then we 'll know. Here's the secret, laying transparent oils on heavy thick ones. Bosch ... not Bosch. The transitions ... Leonardo put on wet paint with the palm of his hand ... dark brown underpainting all the way, and ... that plasticity, that plasticity. And ... and ... if we can get a good reliable particle count, the refraction index on each particle and whether it's isotropic or ... when you get down to the gesso, you ... what was it? What was it? ... You ... yes, the El Greco, I ...