Now, in the fall of 1866, it was a third of what it had been, with a ragged fringe of dilapidated adobes crumbling back into the soil.
The adobes were still in pristine shape in 1866. 
mnli hypothesis: The adobes were still in pristine shape in 1866.  premise: Now, in the fall of 1866, it was a third of what it had been, with a ragged fringe of dilapidated adobes crumbling back into the soil.