The substance of things unseen. Cities, past and future. In Oxford, perhaps we can use Lewis Carroll and look in the looking glass that is New York City to try and see our true selves, or perhaps pass through to another world. Or, in the words of F. Scott Fitzgerald, "As the moon rose higher, the inessential houses began to melt away until gradually I became aware of the old island here that once flowered for Dutch sailors' eyes, a fresh green breast of the new world."
New York - Before the City
Mannahatta's fascinating pre-city ecology of hills, rivers, wildlife when Times Square was a wetland and you couldn't get delivery.