Any officer appointed by the village president and board of trustees may be removed by a vote of four-fifths (4/5) of the board for incompetency or for any neglect, deviation or violation of his duty, whenever the board of trustees deems the interests of the village shall require such removal; provided, that no officer shall be removed as aforesaid without being first notified by the village president or village clerk of such intended removal and the grounds therefor, and shall have the opportunity to exculpate himself before the board from the charges against him. (1904 Code § 29.12)