Almost a thousand horses died in the Lake Ladoga when the water suddenly froze.
This story that took place in 1942, during the siege of Leningrad, was told by Curzio Malaparte in his book Kaputt. While attempting to escape a wildfire, the horses tried to swim across the Lake Ladoga. But their entrance in the water, which was in the supercooled state1, caused the sudden freeze of the lake. The astrophysicist Hubert Reeves was the first one to suggest the hypothesis of supercooling to explain this phenomenon.
1 Supercooling: under certain conditions, and in particular when it contains dissolved gases, water can remain liquid at temperatures below its normal freezing point. Liquid water can then be found at almost −43.6°F (around -40°C), at standard pressure. This state is unstable and the slightest impurity or disturbance may lead to the instant solidification of the water.
Bookcents.blogspot.com – Kaputt: The Horses
Killacan.com – Lake Ladoga
Very interesting. On Youtube you find some examples like https://www.youtube.com/watch?v=uDWdZGIxur4