Here we see several illustrations of John Leighton's proposal to divide Greater London into a series of hexagonal boroughs, as described in his book The Unification of London: The Need and the Remedy.
The book can be found in its entirety in our Hexagonal Library, as digitized by the British Library. The British Library seems to maintain fairly strict and I would even say oppressive rules regarding the reproduction of its images, but I am under the impression from a variety of sources that this book in particular is part of a collection that has been released into the public domain. Regardless, under United States copyright law, exact reproductions of works in the public domain are not protected by copyright, so the particular disposition of this collection under British law would seem to be, for our purposes, a moot point. Nonetheless we thank the British Library for making it available, etc.