Morton Salt's logo features the "Morton Salt Girl," a young girl walking in the rain with an opened umbrella and scattering salt behind her from a cylindrical container of table salt, and is one of the ten best-known symbols in the United States. The company's logo and its motto, "When it rains, it pours", both originating in a 1914 advertising campaign, were developed to illustrate the point that Morton Salt was free flowing even in rainy weather. The company began adding magnesium carbonate as an absorbing agent to its table salt in 1911 to ensure that it poured freely.