13. Facts relevant when right or custom is in question.- Where the question is as to the existence of any right or custom, the following facts are relevant:-
any transaction by which the right or custom in question was created, claimed, modified, recognized, asserted or denied, or which was inconsistent with its existence:
particular instances in which the right or custom was claimed, recognized or exercised, or in which its exercise was disputed, asserted or departed from. Illustration. The question is whether A has a right to a fishery. A deed conferring the fishery on A' s ancestors, a mortgage of the fishery by A' s father, a subsequent grant of the fishery by A' s father, irreconcilable with the mortgage, particular instances in which A' s father exercised the right, or in which the exercise of the right was stopped by A' s neighbours, are relevant facts.