Another way to use a semicolon is to provide an explanation for a statement.
I felt almost as cold in the house; while we had the coal stove, we had no coal.
He complained he was feeling cold; although he had a thick jacket, the rain had soaked through.
We didn't want to cross the desert; while we had supplies, we had no sense of direction.
We were sweltering in the ampitheatre; while it did provide shade, the metal roof radiated an oven-like heat.
