"I know how Veritaserum works, thank you." Robards pulled the cork from the vial, set it down, and dripped several drops into his mouth. He swallowed visibly and looked impatiently at Snape. He crossed his arms in front of his chest and waited a moment. Partly because he wanted to give the Veritsaerum time to take effect, partly because he wanted to get on Robards" nerves a little.