(1) when committed by accident and misfortune, or in doing any lawful act by lawful means, with usual and ordinary caution, and without any unlawful intent; or
(2) when committed by accident and misfortune, in the heat of passion, upon any sudden and sufficient provocation, or upon a sudden combat, when no undue advantage is taken, nor any dangerous weapon used, and when the killing is not done in a cruel or unusual manner.