A State is entitled to enact a comprehensive scheme for the licensing and regulation of motor vehicles using its highways with a view to insuring itself of reasonable compensation for the facilities afforded and to providing adequate protection of the public safety; and such scheme may embrace out-of-State vehicles using the State's highways.[825] Thus legislation limiting the net loads of trucks using the State's highways is valid;[826] as are also, in the absence of national legislation on the subject, State regulations limiting the weight and width of the vehicles themselves, provided such regulations are applied without discrimination as between vehicles moving in interstate commerce and those operating only intrastate.[827] Likewise, a State may deny a certificate of public convenience and necessity to one desiring to operate a common carrier over a particular highway to an out-of-State destination in an adjacent State, on the ground that the specified route is already congested. So it was held in Bradley _v._ Public Utilities Commission of Ohio,[828] in which the Court took cognizance of the full hearing accorded the appellant, and of his failure to choose another route, although he was at liberty to do so. And in Maurer _v._ Hamilton a Pennsylvania[829] statute prohibiting the operation over its highways of any motor vehicle carrying any other vehicle over the head of the operator was upheld in the absence of conflicting Congressional legislation. Similarly, in Welch _v._ New Hampshire[830] a statute of that State establishing maximum hours for drivers of motor vehicles was held not to be superseded by the Federal Motor Carrier Act prior to the effective date of regulations by the Interstate Commerce Commission dealing with the subject. Nor was pendency before the Interstate Commerce Commission of an application under the Motor Carrier Act for a license to operate a motor carrier in interstate commerce found to supersede as to the applicant the authority of a State to enforce "reasonable regulations" of traffic upon its highways. "In the absence of the exercise of federal authority," said the Court, "and in the light of local exigencies, the State is free to act in order to protect its legitimate interests even though interstate commerce is directly affected."[831] And for the same reason New York City was entitled to apply to trucks engaged in the delivery of goods from New Jersey a traffic regulation forbidding the operation on the streets of an advertising vehicle.[832] Said Justice Douglas for the Court: "Many of these trucks are engaged in delivering goods in interstate commerce from New Jersey to New York. Where traffic control and the use of highways are involved and where there is no conflicting federal regulation, great leeway is allowed local authorities, even though the local regulation materially interferes with interstate commerce."[833] Also, the Court has consistently sustained State regulations requiring motor carriers to provide adequate insurance protection for injuries caused by the negligent operation of their vehicles.[834]