To+see+him+toiling+up+the+slope+inch+by+inch,+his+breath+coming+fast,+the+tips+of+his+hoofs+clawing+at+the+ground,+and+his+great+sides+matted+with+sweat,

This passage here can clearly describing a good language. The fact that "toiling" and "breath coming fast" seems very descriptive. It seems to describe that the work is very challenging, and as a matter of face, a good usage of language is used in this passage. Because it is descriptive, we are able visualize that it is very difficult to process this work.