The appeal presents the single question whether the facts of the instant ease bring it within the principle announced in Thompson v. Lumberton, 182 N. C., 260, 108 S. E., 722, or the exception to the general rule as applied in Advertising Co. v. Asheville, 189 N. C., 737, 128 S. E., 149. We have concluded that the case is controlled by the decisions in Thompson v. Lumberton, supra, Turner v. New Bern, *469 187 N. C., 541, 122 S. E., 469, Paul v. Washington, 134 N. C., 363, 47 S. E., 793, Rosenbaum v. New Bern, 118 N. C., 83, 24 S. E., 1, and others of like import.

The general rule is, that equity will not interfere by injunction to test the validity of an alleged unlawful or invalid municipal ordinance. Wardens v. Washington, 109 N. C., 21, 13 S. E., 700; Scott v. Smith, 121 N. C., 94, 28 S. E., 64; Cohen v. Comrs., 17 N. C., 2.

. There is an exception to this general rule, however, as well established as the rule itself, that equity will enjoin the threatened enforcement of an alleged unconstitutional law when it is made manifest that otherwise property rights or the rights of persons would suffer irreparable injury. Advertising Co. v. Asheville, supra. See, also, concurring opinions in Turner v. New Bern, supra, and R. R. v. Goldshoro, 155 N. G, 356, 71 S. E., 514.

The plaintiff could hardly regard the payment under protest of a $100 tax, with adequate legal remedy to recover it back, if unlawful, as an irreparable injury to its business. C. S., 7979; R. R. v. Comrs., 188 N. C., 265, 124 S. E., 560.

Error.