Interspersed throughout his scientific essays for "Natural History" magazine, Gould frequently referred to his nonscientific interests and pastimes. As a boy he collected baseball cards and remained an avid New York Yankees fan throughout his life. As an adult he was fond of science fiction movies, but often lamented their poor storytelling and presentation of science. His other interests included singing baritone in the Boston Cecilia, and he was a great aficionado of Gilbert and Sullivan operas. He collected rare antiquarian books, possessed an enthusiasm for architecture, and delighted in city walks. He often traveled to Europe, and spoke French, German, Russian, and Italian. He sometimes alluded ruefully to his tendency to put on weight.