A marriage may be annulled for any of the following causes, existing at the time of the marriage:
(1) That the party in whose behalf it is sought to have the marriage annulled was between the ages of sixteen and twenty years, if male, or between the ages of fourteen and eighteen years, if female, and the marriage was solemnized without the consent of the parent, guardian or person having authority over the party, unless after attaining the ages of twenty or eighteen years, as the case may be, such party freely cohabited with the other and both lived together as husband and wife;
(2) In a subsequent marriage under article 83, number 2, that the former husband or wife believed to be dead was in fact living and the marriage with such former husband or wife was then in force;
(3) That either party was of unsound mind, unless such party, after coming to reason, freely cohabited with the other as husband or wife;
(4) That the consent of either party was obtained by fraud, unless such party afterwards, with full knowledge of the facts constituting the fraud, freely cohabited with the other as her husband or his wife, as the case may be;
(5) That the consent of either party was obtained by force or intimidation, unless the violence or threat having disappeared, such party afterwards freely cohabited with the other as her husband or his wife, as the case may be;
(6) That either party was, at the time of marriage, physically incapable of entering into the married state, and such incapacity continues, and appears to be incurable. (30a)