The present invention is directed, at least in part, to methods for imagewise patterning of a surface. An alternative method of ensuring that the authorization code of an unsuspecting user is not misappropriated includes adding a circuit to the circuitry of the telephone to ensure that a true dial tone is provided when the user picks up the handset. A second one of the two blowers is downstream of the gas outlet and draws an exhaust gas flow from the combustion chamber.