This Figure 8 probably opened with the park and replaced by the Wildcat, thus existing from 1902 to 1928. So far this theory hasn't been confirmed and the it's existence can only be narrowed as follows:
1902: Earliest possible existence being the park's opening year.
1911: Present on a post card.
1955: The year a employee started working for the park and the Wildcat was the only roller coaster present at that time.