opinion of an expert in regard to genuineness or otherwise of signatures and/or hand writings is purely opinion evidence and such opinion evidence in regard to signatures and/or handwriting will not be considered as an opinion based on exact science as in the case of thumb impressions. In addition, it is necessary to observe that expert's opinion evidence as to handwriting or signatures can rarely, if ever, take the place of substantive evidence. In the well considered view of this Court, the defendant’s signatures on the Vakalat and the Written Statement cannot be considered as signatures of comparable and assured standard as according to the plaintiff even by the date of the filing of the vakalat the defendant is clear in his mind about his stand in regard to the denial of his signatures on the suit promissory note and the endorsement thereon and as the contention of the plaintiff that the defendant might have designedly disguised his signatures on the Vakalat and the Written Statement cannot be ruled out prima facie . The view point being projected by the plaintiff that if the defendant is called upon to furnish his signatures in open Court, he might designedly disguise his signatures while making his signatures on papers in open court is also having considerable force and merit. Unless the defendant makes available to the Court below any documents, with his signatures, of authentic and reliable nature more or less of a contemporaneous period, and unless such documents are in turn made available to the expert along with the suit promissory note, the expert will not be in a position to furnish an assured opinion, in the well considered view of this Court. Further, it is not in dispute that the defendant in his crossexamination has denied his signatures on his vakalat filed in the suit and also could not affirm or say for sure as to whether his signature on the affidavit filed in lieu of examination in chief is his signature or not. There is no point in sending to an expert the documents of doubtful nature and character and add one more piece of unreliable evidence and burden the record by wasting the time and money of the parties. When there are no signatures of