In the first place, it is not improper to observe, that the law of cases of necessity is not likely to be well furnished with precise rules, necessity creates the law, it supersedes rules; and whatever is reasonable and just in such cases, is likewise legal; it is not to be considered as matter of surprise, therefore if, much instituted rule is not to be found on such subjects.

Per Sir W.Scott in The Gratitudine (1801) 3 C Rob 240 at p.266