Chwast’s poster promoting Brooklyn’s turn-of-the-century celebrations in 2000, is, unusually, based on a photograph, in this case the Soldiers’ and Sailors’ Memorial Arch in Grand Army Plaza, dedicated in 1892 as a monument to the fallen of the Civil War. Perhaps predictably, Chwast enlivens this solemn symbol of the borough, an unlikely choice for a celebration in the first place, with colorful typography and cartoon illustrations of fireworks.