in Thoreau’s Journal:

Generally speaking, the autumnal tints affect the color of the landscape for only two or three miles, but I distinguish maples by their color half a mile north of Brooks Clark’s, or some three miles distant, from this hill, —one further east very bright. Also I see them in the northeast, or on or near, apparently, a road between Bedford and Billerica, at least four or five miles distant ! ! This is the furthest I can see them.