“Denver: Past and Present,” by Mark A. Barnhouse (Arcadia Publishing) and “Douglas County: Past and Present,” by Jean Jacobsen and Susan Rocco-McKeel (Arcadia Publishing) “Denver: Past and Present,” by Mark A. Barnhouse (Arcadia Publishing) Then-and-now pictures are always fun. But they can be disturbing when you see a once-elegant old building stripped of its adornments or a wildlife scene replaced by a cheesy housing development.