Three Connected Vessels
This Demonstration shows how three connected vessels fill when they are divided by barriers that can be moved. This is how canal locks work and and is part of the reason the Titanic sank.
 http://www.haworth-village.org.uk. "How a Canal Lock works" (Dec 2015) https://canalrivertrust.org.uk/news-and-views/features/how-do-locks-work.
 Titanic-Titanic.com. "Titanic's Watertight Compartments." (2010) www.titanic-titanic.com/titanic_watertight_compartments.shtml.