Bret Harte 
Openings in the Old Trail [EPUB ebook] 

It was high hot noon on the Casket Ridge. Its very scant shade was restricted to a few dwarf Scotch firs, and was so perpendicularly cast that Leonidas Boone, seeking shelter from the heat, was obliged to draw himself up under one of them, as if it were an umbrella. Occasionally, with a boy’s perversity, he permitted one bared foot to protrude beyond the sharply marked shadow until the burning sun forced him to draw it in again with a thrill of satisfaction.