1. The defendant is in control and possession of the land (Rylands) onto which he brings and accumulates the thing (Giles).
2. The thing would cause mischief if it escaped. (Stannard v Gore)
3. The thing escapes from the land in control and possession of the defendant to land in the control and possession of the claimant (Hale) and causes reasonably foreseeable harm (Cambridge).
4. The defendant’s use of land is non-natural which means extraordinary and unusual in the time and place (Transco).