A cloud tank consists of a bottom layer of salt water and a top layer of fresh water and when various forms of liquid are injected into tank, clouds are produced. 

 

This was the common technique that Hollywood used for decades to capture supernatural weather.  

 

This video is a compilation of as many cloud tank examples as I could think of.  

 

 

And please let me know what movies I may have missed that have cloud tank examples in them.

Music this week by:  
Jesse Ruins from Dream Analysis album
song title: Sofija  
https://jesseruins.bandcamp.com/  (please purchase album if you enjoyed the music)

In Association with: PBS Digital Studios