The following shall be presumed dead for all purposes, including the division of the estate among the heirs:
(1) A person on board a vessel lost during a sea voyage, or an aeroplane which is missing, who has not been heard of for four years since the loss of the vessel or aeroplane;
(2) A person in the armed forces who has taken part in war, and has been missing for four years;
(3) A person who has been in danger of death under other circumstances and his existence has not been known for four years. (n)