209 u.s. Argument for Pe?tion?. ' conflict wi?h Art. I, � par. 5 of the Constitution, which pro- ?ibits the laying of any t?x or duty on articles exported from any State or the giving of any preference by any regulation of commerce or revenue to the ports of one State over those of another. This prohibition' upon exported articles is a guaranty against any form of legislation which burdens exportation. Fairbank v. Un?e.d State?, 181 U.S. 283. The act as construed also violates that portion of the section which prohibits any preference to the ports of one State over these of another, as it gives a distinct preference to those ports which are reached by water as against those which are reached only by land. See Pa?en?er Ca?e?, 7 How. 284, 420; Ward v. Maryland, 12 Wall. 418; Fairbank v. Unitai States, 181 U.S. 283, 294. The contract of the shippers with the Burlington Company was a valid one. A carrier can make a contract to carry for a fixed period at the then published rate?, and such a contract is not subject to the right of-the carrier, voluntarily and with- out the shipper's consent, to change it at any time, upon giving the statutory notice, by an amendment of the tariff. The right to make a change in the tariff is a privilege given to the carrier which it can waive. While it can make no contract that is not subject to a change in the rate by Congress or by finding of the Interstate Commerce C?mmission, it can for itself agrec to carry for a given time at an existing published rate. See pack- ing house contract case (Interstate Commerce Commission v. C. G. W. Ry. Co., 141 Fed. Rcp. 1003); special milk shipper's contract (D., L. & W. R. Go., 147 Fed. Rcp. 51, 61; ecrtiorari denied, 203 U. S. 588). The statute does not in terms interfere with the contractual right of the carrier. Without prohibition by a statute, such a contract is undoub t- edly valid. Cin. &c. R. R. Co. v. Interstate Corn. Commission, 162 U.S. 184; Pond-Decker Lumber Co. v. Spencer, 30 C. C. A. 430; S.C., 86 Fed. Rep. 846, 848; 4 Elliott on Railroads, �60; Memphis & C. Packet Co. v. Abell, 17 Ky. Law Rep. 191; $. C., 30 S. W. Rep. 658, 659; Baldwin v. Liverpool & G. W.
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