More great screengrabs and some (not so great) gabbing to go with them.
These first two drawings were placed together on the DVD but I don't think they were meant to be in continuity together - the blue spots on the second drawing would suggest that they are from the part when Mim is sick, and her attitude when she's sick would be totally different from her attitude in the first sketch.
Here's the cool thing about this sketch: how Bill made it clear she was SNEEZING out the flames and not intentionally spitting fire. If we had the anticipation drawing, that would clarify that action for sure, but here you can tell it's accidental by the way her body is being thrown back, particularly the foot that is up in the air. If Mim was breathing fire in a purposeful, menacing way (as she does before she gets sick) both feet would be on the ground and she would be aggresively leaning forward in a threatening way, I'm sure. Here she's clearly off balance, tossed back as you are when you sneeze. Her expression - especially the way the eye is handled - reads as a sneeze. Her eyebrows would be lowered in a menacing glare if she was angrily directing the fire at Merlin. The gesture of the hand - it looks like it's flinching - seems very accidental as well. If she was being threatening I'm sure it would be more of a fist or a scary-looking claw.
Wart and the Owl almost get cooked.
On this next one, I like how Bill threw Wart and the Owl's faces into silhouette because their expressions are incidental to the meaning of the sketch. The focus is on the letters on the board, not how either one of them feels about it. And you wouldn't really see much of either one of their faces from this angle anyway. The greatest contrast - black on white - is reserved for the area where he wants you to look: the area around their faces and the chalk. The lighting doesn't particularly follow a logical plan but it works well to frame the figures.
Nice composition - the three objects of interest aren't in a straight line. They form a triangle between the gears, Wart and the Owl. There's black-on-white on the gears and on the Owl to help draw your eye, and on the chair above Wart as well. I like how the area in front of his face is clear to give his look some room to breathe. And the areas of clutter and detail - the skull, books, beakers and the rest - are covered with tone to help pull it all together and keep it from distracting from the real emphasis - the two figures and the gears. I can't help but admire the way that box behind the owl's head forms a shape that helps to frame the owl's face. And in a subtle way the shape of the table top and the side of the table seem to form an arrow that points to the machinery.
And lastly....why, that's just a damn fine drawing of a dodo.