LONDON — On January 15, 1759, a full 258 years ago, The British Museum opened its doors to “all studious and curious persons.” It was the first national public museum in the world. Much has since changed for the institution, which reached only 50 visitors a day in the early years. Now the museum reaches over 15,000 visitors daily with an online reach in the millions. Director Hartwig Fischer explains that in the midst of a changing world, the museum’s mission is the same as it has always been. For more information, www.britishmuseum.org.