On that summer day the sky over New York was unflecked by clouds, and the air hung motionless, the waves of heat undisturbed. The city was a vast oven where even the sounds of the coiling traffic in its streets seemed heavy and weary under the press of heat that poured down from above. In Washington Square, the urchins of the neighborhood splashed in the fountain, and the usual midday assortment of mothers, tramps and out-of-works lounged listlessly on the hot park benches. As a bowl, the Square