In this case a rule to show cause was allowed by Mr. Justice Trenchard, why a peremptory or alternative writ of mandamus should not be issued commanding the state board of health of New Jersey to grant the application of the relator, for a permit to erect and maintain a hospital for the care of persons afflicted with pulmonary tuberculosis, in the borough of Hopatcong, Sussex county, New Jersey. At the outset the state insists that certiorari and not mandamus is the proper remedjr. This we think is so. It is not the function of a writ of mandamus to compel the state board of health to perform an act already completed nor to do it in a different way than already done. The writ of mandamus is never granted in a doubtful case. Uszkay v. Dill, 92 N. J. L. 327. At all events the power to issue a writ of mandamus is discretionary. Jones Co. v. Town of Gutlenberg, 66 N. J. L. 58. The application for the writ is denied.