Emotions from a distance

How does Tom Sawyer feel in this snippet?

He wandered far from the accustomed haunts of boys, and sought desolate places that were in harmony with his spirit. A log raft in the river invited him, and he seated himself on its outer edge and contemplated the dreary vastness of the stream, wishing, the while, that he could only be drowned, all at once and unconsciously, without undergoing the uncomfortable routine devised by nature.

How does Tom feel?

Tom clearly feels sad and sorry for himself, lonely, isolated, wanting to die.

We know this from the way Mark Twain describes Tom's thoughts and the way he uses reinforcing details throughout the description.

The distance effect

Notice how Twain doesn't get into too much physical detail in this snippet.

He doesn't write: "Tom sat on the edge of the wide green river, mud sucking at his toes, the air stinking of marsh gas. Mosquitoes landed on the backs of his hands while he contemplated the dreary vastness of the stream…"

Instead he keeps the description at a distance, almost summarising thought and action.

Looking at this snippet another way, it is an emotional portrait of Tom but his emotion is reinforced through the way Mark Twain describes the world around him. 

Here's the same snippet, but with emotional labels and reinforcing details highlighted:

He wandered far from the accustomed haunts of boys, and sought desolate places that were in harmony with his spirit. A log raft in the river invited him, and he seated himself on its outer edge and contemplated the dreary vastness of the stream, wishing, the while, that he could only be drowned, all at once and unconsciously, without undergoing the uncomfortable routine devised by nature.

Now here are some worked examples that use a similar narrative summary approach, and reinforce emotion through descriptive details:

That afternoon they caught a leisurely train to the seaside to enjoy the sunset over the water. Thaddeus bought a bucket of fish and fed a crowd of gulls while happily chatting about his plans to become a detective, and Henry splashed along the water's edge dreaming of what it must be like to be a greyhound.

Before Mizune could leave the village, Carlo, unable to accept the injury to his pride from defeat the day before, challenged her to another duel, and he goaded the villagers into barring her way so that she was forced to face him, reluctantly at first and then with a growing anger for him and all these petty people who would treat a lone swordswoman as sport.

Imagine a scene then zoom out and summarise the action, thoughts, and feelings.

Use detail to reinforce the character's emotions, but don't get bogged down!

Describe a character's emotions from a distant, zoomed out perspective, using summary and a few reinforcing details.