In Orwell's Nineteen Eighty-Four there's the following passage:
He began swallowing spoonfuls of the stew, which, in among its general sloppiness, had cubes of spongy pinkish stuff which was probably a preparation of meat.
"Among" is defined as "in, into, or through the midst of; in association or connection with; surrounded by" (Dictionary.com), so the word itself already contains the notion of being "in".
Why does Orwell write "in among" instead of just "among"? Is there any difference between the two of them? How common is "in among"?