McTeague had told himself that the heat upon the lower slopes of the Panamint had been dreadful; here in Death Valley it became a thing of terror. There was no longer any shadow but his own. He was scorched and parched from head to heel. It seemed to him that the smart of his tortured body could not have been keener if he had been flayed.

"If it gets much hotter," he muttered, wringing the sweat from his thick fell of hair and mustache, "if it gets much hotter, I don' know what I'll do." He was thirsty, and drank a little from his canteen. "I ain't got any too much water," he murmured, shaking the canteen. "I got to get out of this place in a hurry, sure."

By eleven o'clock the heat had increased to such an extent that McTeague could feel the burning of the ground come pringling and stinging through the soles of his boots. Every step he took threw up clouds of impalpable alkali dust, salty and choking, so that he strangled and coughed and sneezed with it.

"LORD! what a country!" exclaimed the dentist.

An hour later, the mule stopped and lay down, his jaws wide open, his ears dangling. McTeague washed his mouth with a handful of water and for a second time since sunrise wetted the flour-sacks around the bird cage. The air was quivering and palpitating like that in the stoke-hold of a steamship. The sun, small and contracted, swam molten overhead.

"I can't stand it," said McTeague at length. "I'll have to stop and make some kinda shade."

The mule was crouched upon the ground, panting rapidly, with half-closed eyes. The dentist removed the saddle, and unrolling his blanket, propped it up as best he could between him and the sun. As he stooped down to crawl beneath it, his palm touched the ground. He snatched it away with a cry of pain. The surface alkali was oven-hot; he was obliged to scoop out a trench in it before he dared to lie down.

This is an excerpt from the end of Frank Norris' novel McTeague, which depicts the title character in the desert. He's fleeing the police after murdering his wife. Bad call, dude.

McTeague's in deep trouble in this excerpt. He's managed to escape the police, who are hunting him for his wife's murder, only to find himself in the middle of Death Valley. It's really hot and he's running out of water. C'mon, man—don't choose a place called "Death Valley" if you want a good chance at survival. Even "Mojave" sounds more hospitable.

Survival is the theme of this passage, and it's also an important theme in a lot of Naturalist literature. Naturalists often depict the struggle for survival, or characters (like McTeague) who are forced to fight for their lives… even after taking the lives of others.

We really get a sense of how hot it is through the narrator's descriptions in this passage. The heat is described as "a thing of terror," McTeague is "scorched and parched from head to heel," and the surface of the soil is "oven-hot." McTeague is almost baking in the heat.

In giving us such a stark impression of the environment in this passage, the narrator makes it clear what McTeague is up against. His very survival is at stake here. These Naturalists were keen on showing readers the full extent of possible suffering—and you can't suffer much more than when you're cooking alive in the desert.