Pictured: A float from the AHA's Tournament of Roses Parade on New Year's Day in 1972, in Pasadena, Calif.

On Jan. 1, 1972, the American Hospital Association participated in the 83rd annual Tournament of Roses Parade in Pasadena, Calif., with this festive float. The entry boasted a giant clock made out of thousands of flowers, and a pair of colorful petal-bedecked circular frames featuring scenes from inside and outside hospitals. The theme was “Night and Day,” a reminder that the nation’s hospitals operate around the clock to serve their communities. Riding the float were nurses, an emergency department technician, a hospital pharmacist and a hospital volunteer. The grand marshal for the 1972 Rose Parade was TV’s champagne maestro himself, Lawrence Welk.