opinion: Mr. Justice Douglas
  delivered the opinion of the Court.
  This is an action brought in the District Court by the United States to enjoin the Union Pacific Railroad Company from drilling for oil and gas on “the right of way” granted it by § 2 of the Act of July 1, 1862, 12 Stat. 489, 491, for the construction of a railroad and telegraph line. The claim of the United States is that “the right of way” granted by the Act is not a grant that includes mineral rights. The District Court’s decision was adverse to the United States. 126 F. Supp. 646. The Court of Appeals affirmed. 230 F. 2d 690. The case is here on a petition for a writ of certiorari which we granted in view of the public importance of the question presented. 352 U. S. 818.
  The “right of way” which was granted by § 2 of the Act was “for the construction of said railroad and telegraph line.” As an aid to the construction of the railroad, “every alternate section of public land” on each side of the road was also granted. § 3. Section 3 further provided “That all mineral lands shall be excepted from the operation of this act . . . .” (Italics added.)
  On the face of the Act it would seem that the use of the words “the right of way” describes a lesser interest than the grant of “public land.” Moreover, this right of way was granted Union Pacific “for the construction of said railroad and telegraph line.” § 2. That purpose is not fulfilled when the right of way is used for other purposes. See Northern Pacific R. Co. v. Townsend, 190 U. S. 267, 271. It would seem that, whatever may be the nature of Union Pacific's interest in the right of way, drilling for oil on or under it is not a railroad purpose within the meaning of § 2 of the Act.
  It would also seem from the words of the Act that, whatever rights may have been included in “the right of way,” mineral rights were excepted by reason of the proviso in § 3 excepting “mineral lands.” The exception of “mineral lands,” as applied to the right of way, may have been an inept way of reserving mineral rights. The right of way certainly could not be expected to take all the detours that might be necessary were it to avoid all lands containing minerals. But that the proviso applies to § 2 as well as to § 3 is plain. While the grant of “the right of way” is made by § 2 and the exception of “mineral lands” is contained in § 3, the exception extends not merely to § 3 but to the entire Act.
  It is said that the exception in § 3 was in terms made applicable to the entire Act merely to leave no doubt that land grants to other railroads, contained in §§ 9, 13 and 14 of the Act, were not to include “mineral lands.” But the exception in § 3 is not limited merely to a few enumerated sections any more than it is limited to § 3. The proviso makes sense if it is read to reserve all mineral rights under the right of way, as well as to reserve mineral lands in the alternate sections of public land granted in aid of the construction of the road. Indeed, we can see no other way to construe it if it is to apply, as it does, not merely to § 3, but to the entire Act, including § 2 which grants the right of way.
  The reservation of the mineral resources of these public lands for the United States was in keeping with the policy of the times. The gold strike in California in 1848 made the entire country conscious of the potential riches underlying the western part of the public domain. The method of asserting federal control over mineral lands was not finally settled until the Act of July 26, 1866, 14 Stat. 251, prescribed the procedure by which mineral lands could be acquired. But meanwhile — from 1849 to 1866 — the federal policy was clear. As the Court said in Mining Co. v. Consolidated Mining Co., 102 U. S. 167, the federal policy during this interim period was to reserve mineral lands, not to grant them. The policy was found to be so “uniform” in this interim period (id., at 175) that the Court, in construing an 1853 Act governing public lands in California, held that a grant to California did not include mineral lands, although they were not specifically excepted.
  The case is much stronger here, for “mineral lands” are specifically reserved. It is, therefore, wholly in keeping with the federal policy that prevailed in 1862, when the present right of way was granted, to construe “mineral lands” to include mineral resources under the right of way. For it was the mineral riches in the public domain that Congress sedulously sought to preserve until it formulated the special procedure by which all mineral resources were to be administered. In United States v. Sweet, 245 U. S. 563, Mr. Justice Van Devanter, our foremost expert on public land law, discussed this policy at length and cited in support of this federal policy the very Act we have under consideration in the present case. Id., p. 569, n. 1. And see Barden v. Northern Pacific R. Co., 154 U. S. 288, 317-318. We would have to forget history and read legislation with a jaundiced eye to hold that when Congress granted only a right of way and reserved all “mineral lands” it nonetheless endowed the railroad with the untold riches underlying the right of way. Such a construction would run counter to the established rule that land grants are construed favorably to the Government, that nothing passes except what is conveyed in clear language, and that if there are doubts they are resolved for the Government, not against it. Caldwell v. United States, 250 U. S. 14, 20-21. These are the reasons we construe “mineral lands” as used in § 3 of the Act to include mineral rights in the right of way granted by § 2.
  The system which Congress set up to effectuate its policy of reserving mineral resources in the alternate sections of public land granted by § 3 was by way of an administrative determination, prior to issuance of a patent, of the mineral or nonmineral character of the lands. Patents were not issued to land administratively determined to constitute mineral lands. And, the administrative determination was final. Burke v. Southern Pacific R. Co., 234 U. S. 669. Such an administrative system was obviously inappropriate to the right of way granted by § 2. The land needed for the right of way was not acquired through the issuance of a patent, but by the filing of a map showing the definite location of the road, followed by its actual construction. Northern Pacific R. Co. v. Townsend, supra, at 270.
  A provision for prior administrative determination of which land in the path of the right of way constituted mineral lands would have been inappropriate for another reason. As already noted, the route of the railroad had to be determined by engineering considerations which could not allow for the extensive detours that the avoidance of land containing minerals would make necessary.
  Because the administrative system, by which the exception of “mineral lands” was administered in relation to the lands granted by § 3, is inappropriate to the right of way granted by § 2, we are urged to conclude that the exception of “mineral lands” in § 3 was not intended to apply to § 2. But, construing the grant in § 2 favorably to the Government, as we must, we cannot conclude that Congress meant the policy it expressed, by excepting “mineral lands” in § 3, to be inapplicable to § 2 in the face of its admonition that the exception is applicable to the entire Act. Nor can we conclude that, because the administrative system, by which mineral resources in the grant of land under § 3 were reserved, was inappropriate to § 2, Congress did not intend appropriate measures to reserve minerals under the right of way granted by § 2. We cannot assume that the Thirty-seventh Congress was profligate in the face of its express purpose to reserve mineral lands.
  To be sure, Congress later on designed a more precise and articulated system for the separation of subsoil rights from the other rights in the western lands. See, for example, the Act of March 3, 1909, 35 Stat. 844. It would have been better draftsmanship, if, in referring to § 2, Congress had used the words “mineral rights” instead of “mineral lands.” Yet it will not do for us to tell the Congress “We see what you were driving at but you did not use choice words to describe your purpose.”
  Some reliance is placed on a line of decisions of the Court which describe the rights of way under early railroad land grants as limited fees. These cases were, for the most part, controversies between the railroad and third persons and involved problems so remote from the present one as to be inapt as citations. For example, the leading case raised the question whether third parties could establish valid homesteads on the railroad right of way after the right of way had been located and the tracks laid. Northern Pacific R. Co. v. Townsend, supra. An answer in favor of the railroad on the ground that it had a limited fee could hardly be an adjudication concerning the ownership of mineral resources underlying the right of way in a contest between the United States and the railroad. In only one of the cases cited was the United States a party; and in that case the question did not involve mineral rights but jurisdiction over a person transporting liquor. If the right of way was Indian Country when it crossed an Indian reservation, then a violation of the liquor laws had occurred. The Court held that the right of way was not Indian Country and said in passing that the right of way constituted the fee in the land. Clairmont v. United States, 225 U. S. 551, 556. We do not stop to examine the other cases using like language to describe the railroad’s right of way, because in none of them was there a contest between the United States and the railroad-grantee over any mineral rights underlying the right of way. The most that the “limited fee” cases decided was that the railroads received all surface rights to the right of way and all rights incident to a use for railroad purposes.
  Great reliance is placed on Great Northern R. Co. v. United States, 315 U. S. 262, for the view that the grant of a right of way in the year 1862 was the grant of a fee interest. In that case we noted that a great shift in congressional policy occurred in 1871: that after that period only an easement for railroad purposes was granted, while prior thereto a right of way with alternate sections of public land along the right of way had been granted. In the latter connection we said, “When Congress made outright grants to a railroad of alternate sections of public lands along the right of way, there is little reason to suppose that it intended to give only an easement in the right of way granted in the same act.” Id., at 278. But we had no occasion to consider in the Great Northern case the grant of a right of way with the reservation of “mineral lands.” The suggestion that a right of way may at times be more than an easement was made in an effort to distinguish the earlier “limited fee” cases. To complete the distinction, Mr. Justice Murphy with his usual discernment added, “None of the cases involved the problem of rights to subsurface oil and minerals.” Id., at 278.
  The latter statement goes to the heart of the matter. There are no precedents which give the mineral rights to the owner of the right of way as against the United States. We would make a violent break with history if we construed the Act of 1862 to give such a bounty. We would, indeed, violate the language of the Act itself. To repeat, we cannot read “mineral lands” in § 3 as inapplicable to the right of way granted by § 2 and still be faithful to the standard which governs the construction of a statute that grants a part of the public domain to private interests.
  Reversed.
  Mr. Justice Whittaker took no part in the consideration or decision of this case.
  To that effect are administrative decisions, by officers of the Interior Department dealing with comparable statutes, that a congressional grant of land “for railroad purposes” does not carry the right to drill for oil or to remove solid minerals. Missouri, Kansas & Texas R. Co., 33 L. D. 470 (Act of July 26, 1866, 14 Stat. 289); Missouri, Kansas & Texas R. Co., 34 L. D. 504 (Act of February 28, 1902, 32 Stat. 43); Use of Railroad Right of Way for Extracting Oil, 56 I. D. 206 (Act of March 3, 1875, 18 Stat. 482); Northern Pacific R. Co., 58 I. D. 160 (Act of July 2, 1864, 13 Stat. 365).
  Railroad Co. v. Baldwin, 103 U. S. 426 (a contest between the owner of the right of way and a settler who took possession before the line was definitely located); Missouri, K. & T. R. Co. v. Roberts, 152 U. S. 114 (a contest between the owner of the right of way and one who claimed the land under a grant from the State); New Mexico v. United States Trust Co., 172 U. S. 171 (an effort by the State to tax the right of way and structures on it in face of an exemption granted by Congress); Union Pac. R. Co. v. Laramie Stock Yards Co., 231 U. S. 190 (whether the grant of the right of way was qualified by a later Act of Congress); Rio Grande W. R. Co. v. Stringham, 239 U. S. 44 (a contest between the owner of the right of way and the owner of a placer patent); Choctaw, O. & G. R. Co. v. Mackey, 256 U. S. 531 (an effort of the owner of the right of way to get an exemption from local taxation for a street improvement that enhanced the value of the railroad use); Missouri, K. & T. R. Co. v. Oklahoma, 271 U. S. 303 (the right of the owner of the right of way to compensation for damage suffered by the construction of crossings).