It is profitable to refer in this connection to Hals bury 's Laws of England, (Fourth Edition), Volume wherein it has been stated that: "The general rule as mat all statutes, other than those which are merely declaratory or which relate only to mat 309 ters of procedure or of evidence, are prima facie prospective, and retrospective effect is not to be given to them unless, by express words or necessary implication, it appears that this was the intention of the legislature It has also been stated in the said volume of Halsbury 's Law of England at page 574 that: "The presumption against retrospection does not apply to legislation concerned merely with matters of procedure or of evidence; on the contrary, provisions of that nature are to be construed as retrospective unless there is a clear indication that such was not the inten tion of Parliament." In Blyth vs Blyth, the wife left the husband in 1954 and lived with the co respondent until August, 1955, when she broke off the association.