The various activities enumerated in section 13(a)(5)--the catching,
taking, propagating, harvesting, cultivating, or farming of aquatic
forms of animal or vegetable life as well as ``the going to and
returning from work'' are materially controlled and affected by the
natural elements. Similarly, the activities of ``first processing,
canning, or packing of such marine products at sea as an incident to, or
in conjunction with, such fishing operations'' are subject to the
natural factors mentioned above. The ``loading and unloading'' of such
aquatic products when performed at sea are also subject to the natural
forces.
