4. When, after marriage, he becomes addicted to habitual drunkenness; 5. When he is guilty of such inhuman treatment as to endanger the life of his wife. [§3414.] A previous law of our state provided that when it was fully apparent to the court that the parties could not live in peace and happiness together, and that their welfare required a separation, a decree of divorce might be granted, but no valid divorce can now be granted for any other cause than for some one of those enumerated above; and this is true, although it may plainly appear that a party has wholly disregarded his marriage vows and obligations in various other ways. [Adultery.] As the direct fact of adultery can seldom be proved, when a divorce is asked on this ground, it will be sufficient if the fact can be shown by circumstances which would be inconsistent with any rational theory of innocence, and such as would lead the guarded discretion of a just mind to the conclusion of the truth of the facts. The disposition of the parties may be shown, with the fact of their being together and having an opportunity to commit the act. [Sidenote: Desertion.] A reasonable cause for desertion must be some wrongful conduct on the part of the other party, and must be of such a serious nature that it would _prima facie_ entitle the party deserting to a divorce. If husband and wife mutually agree to separate, such separation will not constitute ground for divorce, unless the party applying for the divorce, in good faith expresses a desire to live with the other. Where the wife is compelled to leave her husband on account of inhuman treatment, such as would entitle her to a divorce, such desertion cannot be made the basis of proceedings for divorce by the husband, for in such case he and not she is guilty of desertion, and this may be alleged by the wife, with other causes, in seeking a divorce. A wife may be justified in leaving her husband because of his failure to protect her from insult and abuse, and when she leaves him for this cause, her desertion will not be grounds for divorce. [Sidenote: Felony.] A conviction for felony which may be subject to reversal does not constitute ground for divorce, but such conviction must be final and absolute. [Sidenote: Drunkenness.] If a woman marries a man knowing him to be intemperate, though she does so in the hope of reforming him, the courts will not interfere after marriage to grant her relief from the result of her misplaced confidence, but where the habit has been acquired subsequent to the marriage and has become fixed and the husband is habitually drunk, though not in such condition during business hours, it is such habitual drunkenness as will entitle the wife to a divorce. [Sidenote: Cruel treatment.]