What is the definition of “escape” under the principle of Rylands v Fletcher?

Despite this early pronouncement, the plaintiffs point out that many legal commentators have been critical of the “escape” requirement under this strict liability concept. The plaintiffs argue that escape should not mean “escape from control”. Rather, the plaintiffs suggest that the court should adopt a definition that escape means “escape from the place on the defendants’ land where the dangerous thing is intended to be kept and where it can only be safely kept”. While plaintiffs’ counsel is correct in that there has been criticism of the “escape” requirement by legal writers, the requirement that the dangerous thing “escaped from the control of the defendants” remains and is an essential element of a cause of action under the principle of Rylands v. Fletcher, supra. The plaintiffs have pled no facts which suggest that the anhydrous ammonia and/or the train cars escaped from the property owned or controlled by the defendants. The plaintiffs have pled no facts which suggest that the anhydrous ammonia and/or the train cars escaped in the sense of “escape” as is required by the rule in Rylands v. Fletcher.