When a period of four months has elapsed since the date of the last investigative act necessary to ascertain the truth, the president of the investigating chamber may, by petition, refer the matter to that court. The Investigating Chamber may, in the interests of the proper administration of justice, either raise the matter and proceed in accordance with the conditions set out in Articles 201,202,204 and 205, or refer the case back to the examining magistrate or such other magistrate in order to continue the investigation.