Archibald McHarg was the ordinary doer of James McHarg of Keirs. When he died, in July 1774, two bills from McHarg of Keirs were in his possession. One, for £230 sterling, was unendorsed and had been accepted by James McHarg in Tairly. The other was for £264 sterling. McHarg of Keirs argued that it was self-evident that Archibald McHarg had held both of these bills in trust: the first to recover payment, the second as a fund of credit. Keirs petitioned the Court to compel the heirs of Archibald McHarg to either deliver these bills to him or destroy them. The defenders, James McHarg, eldest son of Archibald, and his curators, argued that as these bills had been found in the possession of Archibald McHarg, the burden of proof of possession lay on McHarg of Keirs. Lord Monboddo found that the bills had been put into McHarg's hands by Keirs. The defenders gave representation, and then petitioned the Court to review Monboddo's interlocutors. According to marginalia on the case documents, the Court adhered.

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