168. Test to determine what are fixtures.

Whether an object that has been brought onto the land has become affixed to the premises, and so has become a fixture (or a permanent part of the land)1, is a question of fact which principally depends:

  1.  

    (1)     on the mode and extent of the annexation, and especially on whether the object can easily be removed without injury to itself or to the premises; and

  2.  

    (2)     on the purpose of the annexation (that is to say, whether it was for the permanent and substantial improvement of the premises or merely for a temporary purpose or for the more complete