Whenever the governor shall be of opinion that the public good requires it, he is authorized to offer, by proclamation or in such other manner as he may deem advisable, such reward as he may think the nature of the case requires, not exceeding Two Thousand Dollars ($2,000.00), for the apprehension and arrest of any person who has committed any atrocious offense against the criminal laws, to be paid in no instance until the offender is delivered to the civil authority of the county where the offense was committed, and confined in jail or admitted to bail; or the reward may be conditioned to be paid only upon conviction.