'Snow Derby' and its 4-player version Gottlieb's 1970 'Snow Queen' had an end-of-ball bonus ladder, a feature that began to appear regularly on pinball machines from this point forward. One earlier game that had a bonus ladder is Chicago Coin's 1939 'Nippy'. An Add-a-ball version Gottlieb's 1971 'Bristol Hills' was produced for use in New York State. We show a date for this game of December 1970. One piece of Gottlieb documentation shows a date for this game of December 1971 but Cash Box Jan-2-1971 page 30 reports from California that this game is living up to all expectations. Gottlieb's documentation likely intended to indicate a date of December 1970.