The revocation of a license may be express or implied.
                                             Illustration
         (a) A, the owner of a field, grants a license to B to use a path across it. A, with intent to revoke the license, locks a gate across the path. The license is revoked.br          (b) A, the owner of a field, grants a license to B to stack hay on the field. A lets or sells the field to C. The license is revoked.