opinion: BRYAN, Circuit Judge.
  The appellant railroad carriers published and filed with the Interstate Commerce Commission a rate of 23 cents per hundredweight on tin cans from New Orleans to destination points that included Houston, Tex. While that remained a published rate, appellee shippers were required to pay 70 cents per hundredweight. The shipper in two of these cases brought suit to recover the excess above 23 cents, and in the other the carrier sued to recover a refund of the difference which it had paid to the shipper. The cases were consolidated for trial, as the question in each is the same, and resulted in judgments for the shippers.
  The 23-cent rate was published in the tariff schedules by mistake. The carriers intended to continue in force the pre-existing rate of 70 cents. A result of that mistake was to name a rate from New Orleans to Houston less than the rate in effect between intermediate points and Houston, in violation of the long and short haul clause of the In* terstate Commerce Act. 49 USCA § 4(1); Comp. St. § 8566(1).
  Appellants -liken a published tariff rate to a contract between the carrier and the shipper in support of the argument that a mistake can be corrected so as to give effect to the intention of the parties. A shipper has no voice in the fixing of rates, but must pay the published rate, and can only make claim of reparation on account of a rate that is unjust or discriminatory. The Supreme Court has held that a published tariff rate is to be treated as though it were a statute binding upon both the carrier and the shipper. Penn. R. R. Co. v. International Coal Co., 230 U. S. 184, 33 S. Ct. 893, 57 L. Ed. 1446, Ann. Cas. 1915A, 315. Section 6 of the Interstate Commerce Aet (49 USCA § 6; Comp. St. § 8569) provides that a carrier shall not charge or receive any different compensation, whether greater or less, than that shown by the file and published schedule of rates. It is well settled by Supreme Court decisions that this provision of law must be strictly complied with because it is necessary to carry out the purpose of Congress to prevent unjust discrimination. Gulf, Colorado & Santa Fé R. R. Co. v. Hefley, 158 U. S. 98, 15 S. Ct. 802, 39 L. Ed. 910; New York, New Haven & Hartford R. Co. v. Interstate Commerce Commission, 200 U. S. 361, 26 S. Ct. 272, 50 L. Ed. 515; T. & P. R. R. Co. v. Mugg, 202 U. S. 242, 26 S. Ct. 628, 50 L. Ed. 1011; L. & N. R. R. Co. v. Mottley, 219 U. S. 467, 31 S. Ct. 265, 55 L. Ed. 297, 34 L. R. A. (N. S.) 671; Keogh v. Chicago & N. W. R. R. Co., 260 U. S. 156, 43 S. Ct. 47, 67 L. Ed. 183. In Lamb-Fish Lumber Co. v. Y. & M. V. R. R. Co., 42 I. C. C. 470, the Interstate Commerce Commission announces the rule that proof of error in the publication of rates does not justify a departure from the published rates, even though shippers have full knowledge that the rates were published by mistake, and that decision was cited with approval by the Supreme Court in Davis v. Portland Seed Co., 264 U. S. 403, 424, 44 S. Ct. 380, 68 L. Ed. 762. The carriers cannot defend by showing that published rates, if enforced, would violate the long and short haul clause* and subject them to penalties. Such a showing would only be evidence of intention indicating that a mistake was made. Because of the policy of the law, the rate must be abided by as long as it is included in published schedules of rates. The remedy of the carriers is to apply to the Interstate Commerce Commission to have the rate changed.
  The judgments are affirmed.
instruction: What follows is an opinion from a United States Court of Appeals.
  Intervenors who participated as parties at the courts of appeals should be counted as either appellants or respondents when it can be determined whose position they supported. For example, if there were two plaintiffs who lost in district court, appealed, and were joined by four intervenors who also asked the court of appeals to reverse the district court, the number of appellants should be coded as six.
  When coding the detailed nature of participants, use your personal knowledge about the participants, if you are completely confident of the accuracy of your knowledge, even if the specific information is not in the opinion. For example, if "IBM" is listed as the appellant it could be classified as "clearly national or international in scope" even if the opinion did not indicate the scope of the business. 
  
  Your task concerns the first listed appellant. The nature of this litigant falls into the category "private business (including criminal enterprises)", specifically "transportation". Your task is to determine what subcategory of business best describes this litigant.
choices: railroad boat, shipping shipping freight, UPS, flying tigers airline truck, armored cars other unclear