(u)The learned Government Pleader, strenuously contended that the plaintiff should discharge the burden of proof and establish the title and cannot succeed by picking holes on the deposition of D.W.1 or the documents marked by defendant State through D.W.1. On first blush, this argument appears attractive, but a closer scrutiny, in the light of the factual matrix in the instant case, would reveal that such a submission cannot be countenanced in the instant case. The reason is, the plaintiff has, in fact, produced documents and also oral evidence and discharged their initial burden, as would be evident from the factual matrix and discussions, supra. The burden of proof, no doubt, does not shift, but onus of proof, certainly, shifts. The onus or proof not only shifts, but it also swings like a pendulum from one end of litigation to the other. All these principles of law are too well settled by a long line of authorities. In the instant case, the plaintiff, having discharged their initial burden by producing a two centuries old document and also after letting in evidence of an expert in the field, the onus shifts to the State to rebut the evidence and to discredit the witness. The State did neither. On the contrary, the documents produced by the State and marked through the revenue official, supports the case of the plaintiff. Therefore, the theory of not discharging the burden of proof, as canvassed, does not help the State in the instant case. This takes us to the next aspect of the submission of the Government Pleader.”