821. Occupancy.

Ownership may be acquired by occupancy of a thing without an owner1, for example, the capture of wild animals2, the appropriation of free natural elements such as air and water3, the lawful severance of a thing, for example corn or other emblements, from the soil4, and, perhaps, the finding of a thing absolutely abandoned or irretrievably lost5. Proprietary rights may be affected by contracts made between building contractors and sub-contractors in relation to the ownership of plant equipment left on site during the carrying out of work