1) Dramatic atmosphere source 2) Haunted-house device
Found on
https://www.crosswordclues.com/clue/fog-machine
A fog machine, fog generator, or smoke machine is a device that emits a dense vapor that appears similar to fog or smoke. This artificial fog is most commonly used in professional entertainment applications, but smaller, more affordable fog machines are becoming common for personal use. Fog machines can also be found in use in a variety of industr...
Found on
http://en.wikipedia.org/wiki/Fog_machine
No exact match found.
