The opinion of the court was delivered, January 5th 1874, by

Agnew, J. —

The principal question in this case is whether any of the ordinary school taxes can be required to be applied to a debt contracted for building purposes. There is a noticeable difference between the provision in the Act of 8th May 1854, for collecting the tax for ordinary school purposes, and that for collecting the tax for building purposes. The thirty-third section, providing for the latter, declares that it shall not exceed the amount of the regular annual tax for such year, and shall be applied solely to the purpose of purchasing and paying for the ground and the buildings or erection of buildings thereon. The sections relating to the ordinary annual tax have no restriction, except that to be inferred from the duty of keeping the schools open for at least five months in the year. The building tax cannot be diverted to ordinary purposes; but it is not a consequence that none of the ordinary taxes shall be appropriated to the payment of debts for building. The schools must be kept open for five months every year, and may be longer in the discretion of the directors. So far as debts *457have been contracted for the schools during the discretionary period, before the mandamus execution shall have been issued, it would be improper to give the mandamus the effect to divert the ordinary taxes from the past expenses for the schools. The law having made the appropriation for the past year, it would be unjust to deprive teachers of their salaries, or to omit to pay the necessary expenses, whether the money was in the treasury before or came in after the service of the mandamus. So far, therefore, as the court ordered the mandamus to take up the money in the treasury, or to come in from the ordinary taxes, which ought to be applied to the debts contracted for the' schools during the year gone by, we think they erred. To apply the limit of five months to the past expenses would interfere with a discretion already exercised by the board — a discretion exercised under the law. It would be a harsh rule to give the mandamus a retroactive effect. But we cannot perceive the justice or legal rule which would exempt the surplus of the annual taxes from the payment of debts contracted for buildings; provided it does not prevent the schools from being kept open for five months in the subsequent year. There must be school-houses, while the building tax cannot exceed the amount of the ordinary taxes. It would be just, therefore, that a deficiency of the building-tax should be made up from the ordinary revenue, so far as it will not interfere with the' legal limit of time the schools must be kept open. The future is always within the power of the board, and if they have contracted debts for buildings, so as to interfere with the exercise of their discretion beyond... the five months in the coming or present year, it is in effect their own determination against the exercise of the discretionary power. The current year (1873) was within their power, and the order of the court could properly direct the application of all moneys to the execution not required to pay the necessary expenses of maintaining the schools for five months in that year. So much of the order as diverted the money in, or to come into the treasury, from the payment of the debts contracted for the schools before the notice of the mandamus given to the board, was erroneous. The order of the court of June 26th 1873, making the rule for the attachment absolute, is now directed to be modified according to the views above stated, and it is ordered that the record be remanded to the court below for the purpose of making a final decree according to the principles we have stated; and the costs of this appeal are ordered to be paid by the defendant in error in this case.