A Bubbler? What's a Bubbler?

Author Josh Katz did a fascinating survey of regional terms and words that we use across the United States. The same object can have wildly different terms depending on the area of the country. He published his results in his book SPEAKING AMERICAN: HOW Y'ALL, YOUSE, AND YOU GUYS TALK: A VISUAL GUIDE.

https://www.amazon.com/Speaking-American-Youse-Visual-Guide/dp/0544703391