The piece was by Tchaikovsky and I'll do my best to describe the extract.
Firstly, the tempo was around 120 and starts with a full orchestra playing a descending melody with scalic sequences and the beginning of the first phrase looks a little like this.

After it's done that again, it goes into a quieter section where you get WW instruments with the melody and strings doing scale based countermelodies underneath. It's like call and response. This continues and then gets loader toward the original phrases again.
I'm no good at describing things well but hopefully you can go off what I've got down there.
