Note 7 — Chapter I · YELLOWSTONE—THE GEM OF THE MOUNTAINS
Reading edition
Warm River originates west of the Park, but Firehole is the best example of a really warm river. It does not freeze over in temperatures 50° below zero. There are literally thousands of hot springs in Yellowstone. Dr. A. C. Peale estimated three thousand, while Dr. Arnold Hague said the number probably exceeded twenty-five hundred.