long as they have the intent
to return: for if they cease to have this intention they cease to be
yours, and belong to the first person who takes them; and when they lose
the habit they seem also to have lost the intention of returning.

16 Fowls and geese are not naturally wild, as is shown by the fact that
there are some kinds of fowls and geese which we call wild kinds. Hence
if your geese or fowls are frightened and fly away, they are considered
to continue yours wherever they may be, even though you have lost sight
of them; and any one who keeps them intending thereby to make a profit
is held guilty of theft.

17 Things again which we capture from the enemy at once become ours
by the law of nations, so that by this rule even free men become our
slaves, though, if they escape from our power and return to their own
people, they recover their previous condition.

18 Precious stones too, and gems, and all other things found on the
seashore, become immediately by natural law the property of the finder:

19 and by the same law the young of animals of which you are the owner
become your property also.

20 Moreover, soil which a river has added to your land by alluvion
becomes yours by the law of nations. Alluvion is an imperceptible
addition; and that which is added so gradually that you cannot perceive
the exact increase from one moment of time to another is added by
alluvion.

21 If, however, the violence of the stream sweeps away a parcel of
your land and carries it down to the land of your neighbour it clearly
remains yours; though of course if in the process of time it becomes
firmly attached to your neighbour's land, they are deemed from that time
to have become part and parcel thereof.

22 When an island rises in the sea, though this rarely happens, it
belongs to the first occupant; for, until occupied, it is held to belong
to no one. If, however (as often occurs), an island rises in a river,
and it lies in the middle of the stream, it belongs in common to the
landowners on either bank, in proportion to the extent of their riparian
interest; but if it lies nearer to one bank than to the other, it
belongs to the landowners on that bank only. If a river divides into
two channels, and by uniting again these channels transform a man's land
into an island, the ownership of that land is in no way altered:

23 but if a river entirely leaves its old channel, and begins to run in
a new one, the old channel belongs