Carl Pyrdum's 2010 essay on the internal logic of Gothic manuscript illuminations uses a delightful series of illustrations and sprites from Super Mario Brothers. History at its finest:
If you look carefully (the image above–and all the images in this post–should expand if you click it), you can see that the two initial capitals on the page form separate platforms, not quite touching. The uppermost capital provides support for two vine-like borders, one growing upward and another that downward toward the lower capital. And the vines in turn provide support for little birds who sit atop them.
If it turns out that the hound can leap, too, the rabbit still might be able to get away if he can convince Mario to give up one of his precious oak leaves. Flying creatures are allowed to ascend into the open white space of the medieval manuscript page, as this moth is doing in the top left margin of this very same page:
The poor insect enthusiast beneath can only gaze up wistfully at the moth, unable to get any higher on the page because he's run out of platforms.
Now, this attention to gravity is a general tendency, not an ironclad rule. If you poke around Gothic manuscripts long enough you'll find many exceptions, but probably a lot fewer than you might expect. In fact, I've found that the fancier the manuscript, the more consistently its artists tend to respect gravity's role on the page. Deluxe manuscripts like the Yale Lancelot or the Bodleian Alexander are scrupulous about making sure everything is resting on something that's attached to something that's attached back to one of the anchor points. In fact, the better manuscripts purposefully play with the expectation of downward gravity, creating elaborate and fanciful connections between the objects on the page. Next time I get around to this subject, I'll try to show you some of my favorite examples.
(via Making Light)