Had to do the dreaded battery change in my reliable 1994 Regal. After removing the windshield wiper fluid reservoir and the battery, I noticed a very small diameter line running through a hole in the battery "platter" had frayed and broken in two. It routes up to a connection on top of the engine and down to a softball-sized metal spherical canister mounted to the frame underneath the battery. I started the car and noticed air is being sucked into this line, so I assume it is providing air/oxygen to the engine for combustion. Engine runs fine and there is no check engine light. I disconnected the broken piece of line from the metal sphere canister, but left the remaining line connected to the top of the engine.

Does anyone know what this line is? What about the spherical canister? Is it okay to drive the car with the line broken?