The State Highway Commissioner is hereby authorized to empower the assistant commissioner, the chief engineer, the township commissioner, the executive manager, the principal assistant engineer, the office engineer, the maintenance engineer, the assistant maintenance engineer, the construction engineers, the registrar of motor vehicles, the secretary, and such other employés, to perform such official acts as the State Highway Commissioner may designate: Provided, That this act shall not be construed to relieve the State Highway Commissioner of responsibility for such acts as may be performed by such employés.
71 P.S. § 1375