The Barnes Foundation, an extraordinary collection of art amassed by Albert C. Barnes, has been one of America’s strangest art museums from the day its doors opened in 1925. Barnes’s unique juxtapositions of paintings and objects were intended to help the viewer learn to look closely at art. The original building, in Merion, Pa., closed at the end of June — the collection will be relocated to a new one in Philadelphia next year — but The Times has created an interactive tour of some of the old museum’s highlights