The Counties and Cities on the Gulf Coast being subject to calamitous overflows, and a very large proportion of the general revenue being derived from those otherwise prosperous localities, The Legislature is especially authorized to aid by donation of such portion of the public domain as may be deemed proper, and in such mode as may be provided by law, the construction of Sea Walls, or Breakwaters, such aid to be proportioned to the extent and value of the works constructed, or to be constructed, in any locality.