What Chapter is the scene with the mountain lion in Where the Red Fern Grows?
The scene with the mountain lion occurs in Chapter 19.
In that Chapter, Old Dan and Little Ann tree a bobcat. Although Billy tries to get them away from the ferocious creature, Old Dan will not back down, and fearlessly bays a challenge to the cat. In the brave dog's veins flows "the breeded blood of a hunting hound...(and) in his fighting heart, there is no fear".
The battle which ensues and fierce and bloody. The hounds fight courageously, but are no match for the larger and heavier bobcat. Billy, with tears running down his cheeks, fights "for the lives of (his) dogs" with the only weapon at his disposal, a double-bitted ax. By the time he is able to land a telling blow on the big cat, Old Dan has been mortally wounded.
Despite the efforts of Billy's mother to fix the hound dog's wounds, Old Dan dies. Although Little Ann's injuries are not as extensive, she loses her will to live, pining away for her lifelong companion. It is not long before she, too dies, having dragged herself to Old Dan's grave with the last of her strength (Chapter 19).