Snape gave him a searching look, clearly not satisfied with that non-answer. He refrained from trying to go any deeper than inspecting his expression, not wanting to put him too much on his guard. "No?" he asked softly, vanishing the remains of the potion to make room in the cauldron for his next effort. "And then you - what? Accidentally plunged both arms straight into it? You can have a seat - keep your arms on the table."