Exodus 9:10

9:10 So they took soot from a furnace and stood before Pharaoh, Moses threw it into the air, and it caused festering boils to break out on both people and animals.

Exodus 19:18

19:18 Now Mount Sinai was completely covered with smoke because the Lord had descended on it in fire, and its smoke went up like the smoke of a great furnace, ¹  and the whole mountain shook ²  violently.

[19:18]  ¹ sn The image is that of a large kiln, as in Gen 19:28.

[19:18]  ² tn This is the same word translated “trembled” above (v. 16).