This scene is about the massacre of a band of Indians. Fools Crow can smell the death, and he knows what he is about to see, and he goes into the camp, anyway. He knows that he has to see it to understand it. He even forces Heavy-charging-in-the-bush to take him into the camp when the horse is reluctant. The scene could come right out of a horror novel: the smell of decaying flesh in the air; the eerie, "sharp-edged" sun; dark smoke emanating from the dead lifeless camp. The author uses very descriptive language to illustrate the importance of this scene. The tone is very grim.
James Welch contrasts the white of the snow with the black of the corpses. Fools Crow is sickened by this gruesome scene. We see how he weeps, falls off his horse and vomits, and we can assume that he is crying, since the author refers to him seeing "through his tears." Welch used parallel structure in his description of the bodies for emphasis. Fools Crow was so deeply disturbed by seeing this that he couldn't even bear to open his eyes for a significant amount of time. He didn't want to see what he had seen; not again.
I can only imagine how that scene of death, destruction, and devastation must have affected Fools Crow, especially knowing that it could just have easily been his own camp, and that not too far in the future, it very well could be the camp of the Lone Eaters. It had to have been traumatizing. I would suppose that no Indian would ever dream of causing so much sorrow on an entire establishment of white people. Fools Crow must have initially been disgusted with white men.
Fools Crow is mourning for his fellow Indians-people he did not know, and never would be able to know. He mourns for the indiscriminating cruelty of the white men; they didn't spare women, child or pet. After a while Fools Crow had seen enough. He stopped seeing what was around him. He became desensitized to his surroundings.
...