retrospective operation. But the rule in general is applicable where the object of the statute is to affect vested rights or to impose new burdens or to impair existing obligations. Unless there are words in the statute sufficient to show the intention of the Legislature to affect existing rights, it is "deemed to be prospective only 'nova constitutio futuris formam imponere debet non praeteritis [2 c. Int. 392]". In the words of LORD BLANESBURG, "provisions which touch a right in existence at the passing of the statute are not to be applied retrospectively in the absence of express enactment or necessary intendment." "Every statute, it has been said", observed LOPES, L.J., "which takes away or impairs vested rights acquired under existing laws, or creates a new obligation or imposes a new duty, or attaches a new disability in respect of transactions already past, must be presumed to be intended not to have a retrospective effect". As a logical corollary of the general rule, that retrospective operation is not taken to be intended unless that intention is manifested by express words or necessary implication, there is a subordinate rule to the effect that a statute or a section in it is not to be construed so as to have larger retrospective operation than its language renders necessary. In other words close attention must be paid to the language of the statutory provision for determining the scope of the retrospectivity intended by Parliament."