delivered tbe opinion of the Court:

It thus appears that there ivas a difference of opinion between this public service corporation and the defendant, one of its patrons, as to whether the flat rate or measured service rate ivas in force. That question was determined in Heiskell v. Chesapeake & P. Teleph. Co. 45 App. D. C. 138, where it was ruled that such flat-rate contracts were discriminatory and prohibited by said Public Utilities Act. The defendant insists, nevertheless, that plaintiff may not recover because “the law does not create an implied agreement where an express contract already exists.” Wc think this contention is inconsistent with our ruling in the Heiskell Case. When this service was rendered, the law had fixed the measure of compensation, and the plaintiff was without authority to exact more or receive less. *455The service having been rendered to and accepted by the defendant, recovery may he litid, as repeatedly held by the Supreme Court of the United States. The decisions on the point art' carefully reviewed in Louisville & N. R. Co. v. Maxwell, 237 U. S. 94, 59 L. ed. 853, L.R.A.1915E, 665, P.U.R.1915C, 300, 35 Sup. Ct. Rep. 494, where the court, speaking of the Interstate Commerce Act, said: ‘‘The rate of the carrier duly filed is the only lawful charge. Deviation from it is not permitted upon any pretext. Shippers and travelers are charged with notice of if, and they as well as the carrier must abide by it, unless it is found by the Commission to ho unreasonable. Ignorance or misquotation of rates is not an excuse for paying or charging either less or more than the rate filed.”

The defendant having stated no defense, it follows that the judgment must be affirmed, with costs. Affirmed.