[Sean]

That is tar that you see. These didn't have a cover over them, just filled up with the tar. They would originally be 0.01uF paper capacitors but since they are across the power line they really should be replaced with some AC Line rated capacitors. I use Vishay 0.0047uF XY capacitors in this application in all the radios I restore. You could use the 0.01uF version but they are more than twice the price and I doubt you will notice a difference.

Vishay 440LD47-R at Mouser

Actually this radio would not have had a cloth power cord on it originally. Philco stopped using cloth cords well before 1941 so the one on it was put on by someone else. Doesn't mean you can't use it though.