Traveler’s Notes . . .

Toronto-based Marine Expeditions canceled two five-day Arctic sailings--one last week and one due to begin Monday--after its Marine Discovery ship developed engine trouble. Customers were offered full refunds or rebooking on later cruises, a spokeswoman said. She added that the situation was unrelated to problems with Marine Expeditions’ sibling company, World Cruise Co., which recently announced it would cease operation. . . . Carnival Cruise Lines, the industry’s largest conglomerate, last week began selling cruises at shopping malls. The first kiosk opened at the Parks at Arlington near Dallas with cruise videos, staff to sell cruises to shoppers and computers plugged into the reservation system. . . . The $26-million Millennium Bridge across London’s river Thames was shut down soon after it opened last weekend because it swayed excessively when people crossed it. It is expected to remain closed for weeks while engineers investigate the problem, officials said. The footbridge links St. Paul’s Cathedral to the new Tate Modern art gallery. . . . Three exhibits that opened this weekend: “The Golden Age of Chinese Archeology,” the only West Coast stop for the show of ancient Chinese art, at the Asian Art Museum of San Francisco, through Sept. 11; “Amazon Rising: Seasons of the River,” interactive exhibits and scores of creatures, at the Shedd Aquarium in Chicago, permanent; “Norman Rockwell: Pictures for the American People,” all 322 Saturday Evening Post covers, at the Corcoran Gallery of Art in Washington, D.C., through Sept. 24.