“…llfa principle”, which takes its name from the decision of the House of Lords in Bwllfa and Merthyr Dare Steam Collieries (1891) Ltd v Pontypridd Waterworks Co [1903] AC 426 (“Bwllfa”). What was at issue there was the amount of compensation payable to mine owners under the Waterworks Clauses Act 1847 where undertakers had objected …”
“…which had not in fact materialised. In accordance with the Bwllfa principle (see Bwllfa and Merthyr Dare Steam Collieries (1891) Ltd v Pontypridd Waterworks Co [1903] AC 426), where the court has knowledge of what actually happened, it need not speculate about what might have happened but should base itself on the known facts.…”