The comment about being dressed for the opera is on the right track, maybe by today’s standards, but in 1904, no self-respecting woman would wear a skirt and frilly white blouse to the opera; that was considered casual wear. She would have worn an evening gown. The men would not wear a business suit, they would have worn a Tux, tails, or, at least, a frock coat, not a suit coat like we see in the photo.
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