 The marshy soil of Flushing Meadows needed special consideration during the original 1937 Perisphere construction.The Perisphere, and subsequently the Unisphere, which used the same platform, employed a foundation of 528 pressure-creosoted Douglas fir piles of in length.Before construction of the Unisphere, three piles were tested for structural integrity and all were found to be sound throughout their entire length.