An inspector from the department of weights and measures in a particular city made a routine examination of the gasoline pumps at a service station to check their accuracy. The inspector found that one pump delivered only 4.5 gallons when the meter showed 5 gallons. The inspector sealed the pump and issued a summons ordering the station owner to report to a hearing to be held the following day. The hearing would be conducted by the commissioner of the department of weights and measures. The operator of the service station claimed that the commissioner lacked authority to compel him to appear at the hearing. Does the commissioner have authority to regulate the operation of the service station?