Winchester is listening to Tchaikovsky's Sixth Symphony while he and B.J. are in the Swamp.
Previously, Potter told War Correspondent Aggy O'Shay that he didn't have a painting of B.J. because he has trouble painting teeth. Here, he specifically tells B.J. to "smile for Mildred", guess he got better at painting them.
When trying to paint a picture of a bickering BJ, Hawkeye, Charles, Klinger, Mulcahy and Margaret, Colonel Potter calls them a bunch of swamp rats.
The inhabitants of The Swamp, particularly Hawkeye and Trapper, were known as the Swampmen.
The inhabitants of The Swamp, particularly Hawkeye and Trapper, were known as the Swampmen.