House-Garage Distance Indicator

Houses are quite close to garages, but two hundred years ago the distance between functionally equivalent structures (house-stable) was much greater. Now two hundred years from now, I predict that the HGDI will once more return to 1811 levels. Why do I say this? Well, the smell of gasoline in a sealed tank is almost impossible to discern, but the smell of horse manure in a stable calls much more attention to itself. And in two hundred years we won’t have any gasoline left but we’ll still have horse manure.