Section 11. They may employ such clerical employees as may be necessary for the proper performance of the work of their offices, who shall perform such duties as the commissioners may determine. They may, in the absence from any meeting of the clerk or any deputy assistant clerk designated under section seven of chapter two hundred and twenty-one, appoint a temporary clerk, who may be a commissioner or other suitable person. He shall be sworn by the chairman or presiding commissioner, keep a record of the proceedings, and deliver the same forthwith to the clerk or deputy assistant clerk, who shall enter it upon the records of the commissioners.