Here comes a translation for those of you whose Danish is a bit rusty:
"The Only Studio in Denmark
that offers Picture Taking by Electrical Light
in the Studio if Ordered in Advance
untill 11 P.M.
V. Jensen & Co"
The address and then at the very bottom it states:
"Original Waiting Rooms"
"Toilet and Dressing Rooms"
I would also draw your attention to the half-naked lady, standing on a globe while holding a gigantic light bulp in her hand. Advertising really hasn't changed that much in a 100+ years.