Opinion by

The action of the Supervisors of Whitemarsh Township in rezoning 146 acres of land in the township from AA residential, which requires a minimum lot area of one-half acre per residence, to A residential, which requires one-quarter acre, was accomplished in full compliance with law and was a valid exercise of the authority vested in them. The issuance of the building permit by the Board of Adjustment was pursuant to the valid ordinance and constituted a proper exercise of the powers and duties of the Board. The court below quite correctly refused to hold the ordinance invalid and to disturb the action of the Board. We, too, find no merit in the attack upon the ordinance and upon the board’s order. The ruling below must, therefore, be affirmed.