Christopher Brown has urged me to take a long and meandering walk. Or, at least, his new book, A Natural History of Empty Lots, has inspired one. Sadly, the empty lots I find in my East Austin neighborhood, unlike his, seem not to have been empty for long. One, where it appears a house used to be and will again be soon, contains evidence of humans but hasn’t yet been taken over by plants and animals, as have many of the places Brown describes. There is a toy figure of a man in samurai garb, now one-eyed and one-handed, atop a cinder block. A loose fork. Long and coiled green sacks of sand that have no apparent use except to corral piles of gravel and…