In this frigid fragile capsule That allows you to fly south
before the winter winds trap you  from Cannibal Ox – Pigeon
Lyrics on Rap Genius   Vast is talking about the body (the
“capsule” for the soul), building on a common theme from the
album. Pigeons have bodies that let them fly to warm weather,
but only for so long: like us, they’re “fragile,” mortal,
destined to be trapped by the “winter winds” and become empty,
“frigid” corpses.