Sailboats glide across a sun-dappled harbor while behind them rise the monumental facades of the Panama-Pacific International Exposition — the Tower of Jewels (right) encrusted with its famous "Novagems" catching the light, and the soaring Column of Progress standing sentinel over golden-domed pavilions that transformed San Francisco's waterfront into a world's wonder for ten magnificent months in 1915. This official exposition postcard (no. 1958), published by Cardinell-Vincent Co. of San Francisco, captures the fairgrounds as they appeared from the bay — a view that would vanish almost entirely when the temporary structures were demolished after the fair closed in December 1915, leaving only the Palace of Fine Arts standing. The unused card retains crisp color and sharp detail in the Cardinell-Vincent chromolithographic style, an Official Post Card of the exposition with the PPIE seal embossed in green on the reverse. A cornerstone piece of 1915 San Francisco and World's Fair ephemera.