Denser and denser grew the smoke, and more acrid its smell.

Mimi, towards whom the draught from the open door wafted the smoke, rose up choking, and ran to the inner door, which she threw open to its fullest extent, disclosing on the outside a curtain of thin silk, fixed to the doorposts.

The draught from the open door swayed the thin silk towards her, and in her fright, she tore down the curtain, which enveloped her from head to foot.

Then she ran through the still open door, heedless of the fact that she could not see where she was going.
Adam, followed by Sir Nathaniel, rushed forward and joined her--Adam catching his wife by the arm and holding her tight.

It was well that he did so, for just before her lay the black orifice of the well-hole, which, of course, she could not see with the silk curtain round her head.
The floor was extremely slippery; something like thick oil had been spilled where she had to pass; and close to the edge of the hole her feet shot from under her, and she stumbled forward towards the well-hole.
When Adam saw Mimi slip, he flung himself backward, still holding her.
His weight told, and he dragged her up from the hole and they fell together on the floor outside the zone of slipperiness.