Whenever the board of managers of the Trenton state hospital with the approval of the state board and the state house commission shall determine that lands acquired for the hospital are no longer necessary, the state house commission may sell the same. Notice of the time and place of sale signed by the commission shall be posted at least three weeks before the time appointed in five or more public places in Mercer county, one of which places shall be in the township, ward or city where the lands are situate. The notice shall also be published at least once a week for four consecutive weeks in two newspapers printed and published in Mercer county, of which one shall be printed and published in Trenton. The last publication shall be not more than seven days prior to the time of sale. At the time appointed, between the hours of twelve and five in the afternoon the commission shall sell the lands at public vendue to the highest bidder. The commission may adjourn the sale from time to time. On receiving the purchase price from a purchaser the commission shall make, execute and deliver in the name of the state a deed conveying the lands. The purchase money after deducting the expenses of sale shall be paid into the state treasury.