" Pa tugged him onto the grass. Pa rolled him over and he flopped where he was rolled. Pa felt his wrist and listened at his chest and then Pa lay down beside him.
“He’s breathing,” Pa said. “He’ll be all right, in the air. I’m all right, Caroline. I’m plumb tuckered out, is all.”
“Well!” Ma scolded. “I should think you would be! Of an the senseless performances! My goodness gracious! scaring a body to death, all for the want of a little reasonable care! My goodness! I--” She covered her face with her apron and burst out crying.
That was a terrible day.
“I don’t want a well,” Ma sobbed. “It isn’t worth it. I won’t have you running such risks!”
Mr. Scott had breathed a kind of gas that stays deep in the ground. It stays at the bottom of wells because it is heaver than the air. It cannot be seen or smelled, but no one can breathe it very long and live. Pa had gone down into that gas to tie Mr. Scott to the rope, so that he could be pulled up out of the gas.
When Mr. Scott was able, he went home. Before he went he said to Pa: “You were right about that candle business, Ingalls. I thought it was all foolishness and I would not bother with it, but I’ve found out my mistake.”
“Well,” said Pa, “where a light can’t live, I know I can’t. And I like to be safe when I can be. But all’s well that ends well. "

― Laura Ingalls Wilder , Little House on the Prairie (Little House, #3)