opinion: Justice Stevens
  delivered the opinion of the Court.
  In 1928, Mountain States Telephone and Telegraph Company purchased an easement from the Pueblo of Santa Ana for a telephone line. Mountain States contends that the conveyance of this easement was valid under §17 of the Pueblo Lands Act of 1924, 43 Stat. 641, because it was “first approved by the Secretary of the Interior.” The Pueblo contends that §17 only authorizes such transfers “as may hereafter be provided by Congress,” and that Congress never provided legislation authorizing the conveyance of Pueblo lands with the approval of the Secretary. Both constructions find some support in the language of § 17.
  I — I
  Congress enacted the 1924 legislation “to provide for the final adjudication and settlement of a very complicated and difficult series of conflicting titles affecting lands claimed by the Pueblo Indians of New Mexico.” The Committee Reports review the unique and “interesting history of the Pueblo Indians” and explain why special remedial legislation was necessary.
  “These Indians were found by Coronado and the first Spanish explorers in 1541, many of them residing in villages and occupying the same lands that the Pueblo Indians now occupy.” From the earliest days, the Spanish conquerors recognized the Pueblos’ rights in the lands that they still occupy, and their ownership of these lands was confirmed in land grants from the King of Spain. Later, the independent Government of Mexico extended limited civil and political rights to the Pueblo Indians, and confirmed them in the ownership of their lands.
  The United States acquired the territory that is now New Mexico in 1848 under the Treaty of Guadalupe-Hidalgo. During the period between 1848 and 1910, when New Mexico became a State, inhabitants of that territory — and members of the bar who advised them — generally believed that the Pueblo Indians had the same unrestricted power to dispose of their lands as non-Indians whose title had originated in Spanish grants. This view was supported by decisions of the Supreme Court of the Territory of New Mexico, and by this Court’s square holding in United States v. Joseph, 94 U. S. 614 (1877), that the Pueblo Indians were not an “Indian tribe” protected by the Nonintercourse Act. As a result, it was thought that the Pueblo Indians could convey good title to their lands notwithstanding the Act’s prohibition of any “purchase, grant, lease, or other conveyance of lands . . . from any . . . tribe of Indians.” 4 Stat. 730, 25 U. S. C. §177.
  The prevailing opinion concerning the unique status of the Pueblo Indians was drawn into question as a result of the attempt by federal authorities to regulate the liquor trade with the Pueblos. They orginally brought charges under an 1897 criminal statute prohibiting the sale of liquor to any “Indian.” Relying on Joseph, however, the Territorial Supreme Court held, in 1907, that the Pueblos were not “Indians” within the meaning of the statute. In response, the New Mexico Enabling Act of 1910 expressly required that the new State’s Constitution prohibit “the introduction of liquors into Indian country, which term shall also include all lands now owned or occupied by the Pueblo Indians of New Mexico.” In United States v. Sandoval, 231 U. S. 28 (1913), the Court noted that whatever doubts there previously were about the applicability of the Indian liquor statute to the Pueblos, “Congress, evidently wishing to make sure of a different result in the future, expressly declared” in the Enabling Act that “it should include them.” 231 U. S., at 38.
  The narrow question decided in the Sandoval case was that the dependent status of the Pueblo Indians was such that Congress could expressly prohibit the introduction of intoxicating liquors into their lands under its power “To regulate Commerce . . . with the Indian Tribes.” U. S. Const., Art. I, § 8, cl. 3. In reaching that decision, however, the Court rejected the factual premises that had supported its judgment in Joseph, and suggested that “the observations there made respecting the Pueblos were evidently based upon statements in the opinion of the territorial court, then under review, which are at variance with other recognized sources of information, now available, and with the long-continued action of the legislative and executive departments.” 231 U. S., at 49. The Court’s disapproval of Joseph strongly implied that the restraints on alienation contained in the Nonintercourse Act — as well as the liquor statute — might apply to the Pueblos. As a result, the validity of all non-Indian claims to Pueblo lands was placed in serious doubt.
  Relying on the rule established in Joseph, 3,000 non-Indians had acquired putative ownership of parcels of real estate located inside the boundaries of the Pueblo land grants. The Court’s decision in Sandoval cast a pall over all these titles by suggesting that the Pueblos had been wrongfully dispossessed of their lands, and that they might have the power to eject the non-Indian settlers. After conducting extensive hearings on the problem, Congress drafted and enacted the Pueblo Lands Act of 1924. The stated purpose of the Act was to “settle the complicated questions of title and to secure for the Indians all of the lands to which they are equitably entitled.” S. Rep. No. 492, 68th Cong., 1st Sess., 5 (1924).
  II
  Under the Act, a Public Lands Board, composed of the Secretary of the Interior, the Attorney General, and a third person to be appointed by the President of the United States, was established to determine conflicting claims to the Pueblo lands. § 2, 43 Stat. 636. The Board was instructed to issue a report setting forth the metes and bounds of the lands of each Pueblo that were found not to be extinguished under the rules established in the Act. Ibid. Continuous, open, and notorious adverse possession by non-Indian claimants, coupled with the payment of taxes from 1889 to the date of enactment in 1924, or from 1902 to 1924 if possession was under color of title, sufficed to extinguish a Pueblo’s title. §4. The Board’s reports were to be implemented by suits to quiet title in the United States District Court for the District of New Mexico. §§ 1, 3.
  The Act also directed the Board to award the Pueblos compensation for the value of any rights that were extinguished if they “could have been at any time recovered for said Indians by the United States by seasonable prosecution.” §6. Settlers who had occupied their lands in good faith, but whose claims were rejected, might receive compensation for the value of any improvements they had erected on their lands, or for the full value of their lands if they had purchased those lands and entered them before 1912 under a deed purporting to convey title. §§ 7, 15.
  After the Board determined who owned each parcel of land, the Act foresaw that some consolidation of each Pueblo’s land holdings might occur. The Board was directed to identify any parcels adjacent to a Pueblo settlement that should be purchased from non-Indian owners for transfer to the Pueblo. §8. In addition, §16 of the Act authorized the Secretary of the Interior, with consent of the Pueblo, to sell any lands owned by the Pueblo that were “situate among lands adjudicated or otherwise determined in favor of non-Indian claimants and apart from the main body of the Indian land.”
  The foregoing provisions of the Pueblo Lands Act were all designed to settle the consequences of past transactions. In contrast, the section we must construe in this case — § 17— was entirely concerned with transactions in Pueblo lands that might occur in the future. It provides:
  “No right, title, or interest in or to the lands of the Pueblo Indians of New Mexico to which their title has not been extinguished as hereinbefore determined shall hereafter be acquired or initiated by virtue of the laws of the State of New Mexico, or in any other manner except as may hereafter be provided by Congress, and no sale, grant, lease of any character, or other conveyance of lands, or any title or claim thereto, made by any pueblo as a community, or any Pueblo Indian living in a community of Pueblo Indians, in the State of New Mexico, shall be of any validity in law or in equity unless the same be first approved by the Secretary of the Interior.” 43 Stat. 641-642 (emphasis added).
  The question to be decided here is whether the second clause — the language following the word “and” — indicates that a Pueblo may convey good title to its lands with the approval of the Secretary of the Interior.
  I — I J-H HH
  In 1905 Mountain States’ predecessor allegedly acquired a right-of-way and constructed a telephone line across land owned by the Pueblo of Santa Ana. App. 8. Presumably the 1905 conveyance would have been invalid under the Non-intercourse Act. See n. 17, swpra. In all events, in 1927 the United States, acting as guardian for the Pueblo of Santa Ana, brought an action in the United States District Court for the District of New Mexico to quiet title to the lands of that Pueblo.
  While the litigation was pending, the Pueblo entered into a right-of-way agreement with Mountain States granting it an easement “to construct, maintain and operate a telephone and telegraph pole line” on the land now in dispute. App. 39. The agreement was forwarded to the Secretary of the Interior by the Bureau of Indian Affairs with the recommendation that it be approved under § 17. Id., at 181-183. This agreement was approved, and the approval was received, and endorsed on the right-of-way agreement. Id., at 43. On the Government’s motion, id., at 36, the District Court thereafter dismissed Mountain States from the quiet title action on the ground that it had “secured good and sufficient title to the right of way and premises in controversy ... in accordance with the provisions of Section 17 of the Pueblo Lands Act.”
  Mountain States removed the telephone line in 1980. On October 10 of that year, the Pueblo brought this action claiming trespass damages for the period prior to the removal of the line. The District Court granted partial summary judgment for the Pueblo on the issue of liability, holding that the grant of the right-of-way in 1928 was not authorized by § 17. Id., at 86-92.
  The Court of Appeals allowed an interlocutory appeal under 28 U. S. C. § 1292(b) and affirmed. 734 F. 2d. 1402 (CA10 1984). The court held that Pueblo lands were protected by the Nonintercourse Act prior to 1924 and that § 17 of the Pueblo Lands Act did not authorize any conveyance of such lands. It reasoned:
  “The two clauses of § 17 of the Pueblo Lands Act are joined by the conjunctive ‘and.’ To us that means exactly what it says. No alienation of the Pueblo lands shall be made ‘except as may hereafter be provided by Congress’ and no such conveyance ‘shall be of any validity in law or in equity unless the same be first approved by the Secretary of the Interior.’ Two things are required. First, the lands must be conveyed in a manner provided by Congress. Second, the Secretary of the Interior must approve. As to the first, at the time of the agreement between the Pueblo and [Mountain States], Congress had provided nothing. Hence, the first condition was not met. The fact that Congress had provided no method makes the approval of the Secretary meaningless. The operation of the second clause depends on compliance with the first clause.” Id., at 1406.
  The Court of Appeals considered and rejected Mountain States’ reliance on the legislative history of the 1924 Act and its construction by the Secretary of the Interior.
  Our concern that the Court of Appeals’ interpretation of the Act might have a significant effect on other titles acquired pursuant to § 17 led us to grant certiorari. 469 U. S. 879 (1984). We now reverse.
  HH <
  The word “hereafter” in the first clause of § 17 supports the Court of Appeals’ interpretation of the Act. Read literally, the statute seems to state unequivocally that no interest in Pueblo lands can be acquired “except as may hereafter be provided by Congress” — or, stated somewhat differently, until Congress enacts yet another statute concerning the lands of the Pueblo Indians of New Mexico.
  The problem with this construction of the statute is that the requirement of the Secretary’s approval in the second clause of § 17 would be a nullity until Congress acts. Even if a later Congress did enact another statute authorizing the alienation of Pueblo lands, that Congress would be entirely free to accept or reject that requirement. Neither the Pueblo nor the Court of Appeals has offered any plausible reason for attributing this futile design to the 68th Congress. In light of “the elementary canon of construction that a statute should be interpreted so as not to render one part inoperative,” Colautti v. Franklin, 439 U. S. 379, 392 (1979), the second clause of § 17 cannot be read as limiting the power of Congress to legislate in the “hereafter.”
  The Court of Appeals’ literal interpretation of the first clause of § 17 would also nullify the effect of § 16. See n. 18, supra. The design of the Pueblo Lands Act indicates that Congress thought some consolidation of Pueblo land holdings might be desirable in connection with the claims settlement program to be promptly implemented by the Pueblo Lands Board. See supra, at 245-246. To this end, § 16 purports to authorize conveyances of Pueblo lands with the consent of the governing authorities of the Pueblo and the approval of the Secretary of the Interior. If the Court of Appeals’ literal construction of § 17 were accepted, the consolidation of properties foreseen by § 16 could have been implemented only as Congress might thereafter provide. It is inconceivable that Congress would have inserted § 16 in the comprehensive settlement scheme provided in the Act if it did not expect it to be effective forthwith.
  Finally, the practical effect of the Court of Appeals’ interpretation is to apply the requirements of the Nonintercourse Act to voluntary transfers of Pueblo lands. In 1924, Congress logically could have adopted any of three approaches to voluntary transfers. It could have left the matter to be decided by the courts; applied the rule of the Nonintercourse Act; or adopted a new rule of law. A review of the structure of the statute convinces us that Congress followed the last course.
  In arguing that § 17 simply extended the provisions of the Nonintercourse Act to the Pueblos, the Pueblo relies on language in the first clause of the section. However, it is the second — not the first — clause of § 17 that closely resembles the language and structure of the Nonintercourse Act:
  Section 17:
  “[N]o sale, grant, lease of any character, or other conveyance of lands, or any title or claim thereto, made by any pueblo as a community, or any Pueblo Indian living in a community of Pueblo Indians, in the State of New Mexico, shall be of any validity in law or in equity unless the same be first approved by the Secretary of the Interior.” Nonintercourse Act:
  “[N]o purchase, grant, lease, or other conveyance of lands, or of any title or claim thereto, from any Indian nation or tribe of Indians, shall be of any validity in law or equity, unless the same be made by treaty or convention entered into pursuant to the Constitution.”
  The language is slightly — but significantly — altered to provide for approval by the Secretary of the Interior instead of ratification by Congress.
  In any case, if Congress had intended to apply the Nonin-tercourse Act to these lands, it is difficult to understand why it did not say so in simple language. When Congress considered it appropriate in the Act to extend generally applicable Indian statutes to the Pueblos it did so with concise language directed to that end. Indeed, in view of subsequent events, Congress might have achieved that result simply by omitting § 17 from the Act and leaving the matter to the courts. See n. 17, supra. In our view, it is much more likely that Congress intended to authorize a different procedure for Pueblo lands in view of their unique history — a history that is discussed at some length in the Committee Reports.
  V
  There is another reading of the statute that better harmonizes the two clauses of § 17 with the structure of the entire Act and with “its contemporary legal context.” After the Joseph decision, it was generally assumed that questions of title to Pueblo lands were to be answered by reference to New Mexico law, rather than to federal law. In 1924, Congress was legislating without the benefit of a clear holding from this Court that the Pueblos had been completely assimilated to the status of Indian tribes whose land titles were protected by federal law. Sandoval had established that the Indian liquor law applied to the Tribe, and had strongly implied that the Nonintercourse Act would also apply; but Congress surely wanted to make clear that state law, for the future, was entirely pre-empted in this area, and that Congress had assumed complete jurisdiction over these lands. The first clause of §17 is fairly read as a flat prohibition against reliance on New Mexico law in connection with future transactions involving Pueblo lands. After 1924, alienation of those lands, voluntary or involuntary, was only to occur if sanctioned by federal law.
  While the first clause of § 17 refers generally to the acquisition of any “right, title, or interest in . . . lands of the Pueblo Indians,” the second clause refers to any “sale, grant, lease ... or other conveyance of lands.” This language plainly refers to transfers of land freely made by a Pueblo. The second clause of § 17 is logically interpreted as providing a firm command, as a matter of federal law, that no future conveyance should be valid without the approval of the Secretary of the Interior. The language suggests that Congress assumed that the Secretary of the Interior could adequately protect the interests of the Pueblos in connection with future land transactions. This construction is supported by the language of § 16 allowing for the consolidation of Pueblo lands with the consent of the Pueblo and if “the Secretary of the Interior deems it to be for the best interest of the Indians.”
  This interpretation of §17 gives both clauses a meaning that is consistent with the remainder of the statute and with the historical situation of the Pueblos. It is consistent with the limited legislative history available, and is supported by the contemporaneous opinion of the Secretary of the Interior and the Federal District Judge who placed a stamp of approval on this transaction and numerous others in the years following the enactment of the Pueblo Lands Act in 1924. The uniform contemporaneous view of the Executive Officer responsible for administering the statute and the District Court with exclusive jurisdiction over the quiet title actions brought under the Pueblo Lands Act “is entitled to very great respect.” These individuals were far more likely to have had an understanding of the actual intent of Congress than judges who must consider the legal implications of the transaction over half a century after it occurred.
  The judgment of the Court of Appeals is reversed.
  It is so ordered.
  Justice Powell took no part in the decision of this case.
  43 Stat. 641. See infra, at 246, for the complete text of § 17.
  S. Rep. No. 492, 68th Cong., 1st Sess., 3 (1924).
  Ibid. The House Report incorporates the Senate Report in verbatim text. H. R. Rep. No. 787, 68th Cong., 1st Sess. (1924).
  S. Rep. No. 492, at 3.
  The 1924 Act affected “20 Pueblos . . . with a total Indian population of between 6,500 and 8,000. Each Pueblo consists of about 17,000 acres of land within its exterior boundaries, or a total of 340,000 acres in all.” Ibid.
  Treaty of Peace, Friendship, Limits, and Settlement between the United States of America and the Mexican Republic, 9 Stat. 922.
  United States v. Lucero, 1 N. M. 422 (1869); Pueblo of Nambe v. Romero, 10 N. M. 58, 61 P. 122 (1900); cf. United States v. Mares, 14 N. M. 1, 88 P. 1128 (1907).
  In concluding that the Pueblos were excluded from the coverage of the Nonintercourse Act, the Court primarily relied upon its understanding of Pueblo culture:
  “ ‘For centuries . . . the pueblo Indians have lived in villages, in fixed communities, each having its own municipal or local government. . . . [T]hey are a peaceable, industrious, intelligent, honest, and virtuous people. They are Indians only in feature, complexion, and a few of their habits; in all other respects superior to all but a few of the civilized Indian tribes of the country, and the equal of the most civilized thereof. . . .’
  “. . . When it became necessary to extend the laws regulating intercourse with the Indians over our new acquisitions from Mexico, there was ample room for the exercise of those laws among the nomadic Apaches, Comanches, Navajoes, and other tribes whose incapacity for self-government required both for themselves and for the citizens of the country this guardian care of the general government.
  “The pueblo Indians, if, indeed, they can be called Indians, had nothing in common with this class. The degree of civilization which they had attained centuries before, their willing submission to the laws of the Mexican government. . . and their absorption into the general mass of the population ... all forbid the idea that they should be classed with the Indian tribes for whom the intercourse acts were made . . . .” United States v. Joseph, 94 U. S., at 616-617 (quoting United States v. Lucero, 1 N. M., at 453).
  The current version of the Nonintercourse Act was enacted as § 12 of the Trade and Intercourse Act of 1834:
  “[N]o purchase, grant, lease, or other conveyance of lands, or of any title or claim thereto, from any Indian nation or tribe of Indians, shall be of any validity in law or equity, unless the same be made by treaty or convention entered into pursuant to the Constitution.” 4 Stat. 730, 25 U. S. C. § 177.
  Section 12 of the 1834 Act is the last in a series of enactments beginning with § 4 of the Indian Trade and Nonintercourse Act of 1790. 1 Stat. 138. See County of Oneida v. Oneida Indian Nation of New York, 470 U. S. 226, 231-232 (1985). In 1851, Congress extended the provisions of “the laws now in force regulating trade and intercourse with the Indian tribes” to “the Indian tribes in the Territor[y] of New Mexico.” 9 Stat. 587.
  29 Stat. 506.
  United States v. Mares, 14 N. M., at 4, 88 P., at 1129.
  36 Stat. 558.
  “[B]y an uniform course of action beginning as early as 1854 and continued up to the present time, the legislative and executive branches of the Government have regarded and treated the Pueblos of New Mexico as dependent communities entitled to its aid and protection, like other Indian tribes, and, considering their Indian lineage, isolated and communal life, primitive customs and limited civilization, this assertion of guardianship over them cannot be said to be arbitrary but must be regarded as both authorized and controlling.” 231 U. S., at 47.
  “These hearings disclosed that there are now approximately 3,000 claimants to lands within the exterior boundaries of the Pueblo grants. The non-Indian claimants with their families comprise about 12,000 persons. With few exceptions, the non-Indian claims range from a town lot of 25 feet front to a few acres in extent. It was stated, however, in the hearings by all parties that probably 80 percent of the claims are not resisted by the Indians and only about 20 percent pf the number will be contested.” S. Rep. No. 492, at 5.
  “The fact that the United States may... at any time in the future take steps to oust persons in possession of lands within these Pueblo grants, and the continuing uncertainty as to title, has cast a cloud on all lands held by white people within the Pueblo areas. . . . The mortgage value of the lands is almost nothing; [and] sales, leases, and transfers have been discontinued . . . Hearings on S. 3865 and S. 4223 before the Subcommittee Considering Bills Relative to the Pueblo Indian Lands of the Senate Committee on Public Lands and Surveys, 67th Cong., 4th Sess., 51 (1923) (Senate Hearings) (report submitted with the testimony of R. E. Twitchell, Special Assistant to the Attorney General).
  Ibid.; Hearings on H. R. 13452 and H. R. 13674 before the House Committee on Indian Affairs, 67th Cong., 4th Sess. (1923).
  The Act itself did not purport to resolve the question whether the Non-intercourse Act applied to the Pueblos; § 4 provided that the statutes of limitations in that section were “in addition to any other legal or equitable defenses which [the claimants] may have or have had under the laws of the Territory and State of New Mexico.” 43 Stat. 637. In November 1924 the Government docketed an appeal in this Court arguing that the Pueblos had always been wards of the United States, and that adverse judgments entered in 1910 and 1916 in quiet title actions brought by the Pueblo of Laguna could not bar a later quiet title action brought by the United States on the Pueblo’s behalf concerning the same parcel of real estate. The Government filed a motion to expedite consideration of the case, informing the Court of the enactment of the Pueblo Lands Act, and noting that “[t]he Chairman [of the Pueblo Lands Board] has informed the Attorney General that an early determination of this ease will be helpful to the Board in the discharge of its duties and functions under this Act.” Motion to Advance of United States, O. T. 1925, No. 208, p. 2. In holding that the quiet title action was not barred, the Court expressly observed that the Pueblos were “Indian tribes” within the meaning of the Nonintercourse Act. United States v. Candelaria, 271 U. S. 432, 441-442 (1926). The practical result was that non-Indian claimants to Pueblo lands could only raise the defenses set out in §4. Unlike Candelaria, the present controversy involves a transaction that occurred after the passage of the Pueblo Lands Act and which is therefore governed by § 17.
  The complete text of § 16 provides:
  “That if any land adjudged by the court or said lands board against any claimant be situate among lands adjudicated or otherwise determined in favor of non-Indian claimants and apart from the main body of the Indian land, and the Secretary of the Interior deems it to be for the best interest of the Indians that such parcels so adjudged against the non-Indian claimant be sold, he may, with the consent of the governing authorities of the pueblo, order the sale thereof, under such regulations as he may make, to the highest bidder for cash; and if the buyer thereof be other than the losing claimant, the purchase price shall be used in paying to such losing claimant the adjudicated value of the improvements aforesaid, if found under the provisions of section 15 hereof, and the balance thereof, if any, shall be paid over to the proper officer, or officers, of the Indian community, but if the buyer be the losing claimant, and the value of his improvements has been adjudicated as aforesaid, such buyer shall be entitled to have credit upon his bid for the value of such improvements so adjudicated.”
  The consideration paid for the easement was $101.60 or 80 cents a pole for 127 poles. App. 181.
  The Government’s motion read in part:
  “[Subsequent to the institution of this suit [Mountain States] has obtained a deed from the Pueblo of Santa Ana approved April 13,1928, by the Secretary of the Interior in accordance with Section 17 of the Pueblo Lands Act of June 7, 1924, and . . . thereby [Mountain States] has obtained, for an adequate consideration, good and sufficient title to the right of way in controversy herein between [the Pueblo] and [Mountain States].” Id,., at 36.
  Id,., at 37. Mountain States has argued that the 1928 dismissal precludes the Pueblo from challenging the validity of the 1928 right-of-way agreement. Brief for Petitioner 39-47. The Court of Appeals held that the dismissal of the quiet title action in 1928 was not a ruling on the merits that would bar this action. 734 F. 2d 1402, 1407-1408 (CA10 1984). In view of our disposition of the case, however, we do not evaluate the merits of this contention.
  Congress did pass Acts in 1926, 44 Stat. 498 and 1928, 45 Stat. 442, authorizing the condemnation of rights-of-way over Pueblo lands, but these Acts were enacted in response to Pueblos that refused to make voluntary conveyances of easements to utilities and common carriers. See H. R. Rep. No. 955, 69th Cong., 1st Sess., 2 (1926). Thus, the 1926 and 1928 Acts were designed to supplement the authority provided in the second clause of § 17, not replace it.
  For example, § 4 of the Act recognized that a Pueblo might bring its own action to quiet title “Provided, however, That any contract entered into with any attorney or attorneys by the Pueblo Indians of New Mexico, to carry on such litigation shall be subject to and in accordance with existing laws of the United States.” 43 Stat. 637; S. Rep. No. 492, at 7.
  Francis Wilson, a representative for the Pueblos, apparently originated the first draft of § 17. In a letter to the Commissioner of Indian Affairs he explained that “Section 17 of the Bill is, we think the shortest way to prevent present conditions from recurring or existing again. . . . This section is intended to cover the same ground as [the Nonintercourse Act] but it is changed so as to accord with the conditions of the Pueblo Indians.” App. to Brief in Opposition 12.
  See Cannon v. University of Chicago, 441 U. S. 677, 699 (1979).
  The Pueblo argues that the specific authority conferred by § 16 would be superfluous if § 17 is interpreted as generally authorizing conveyances with the approval of the Secretary. Provisions similar to § 16, however, were contained in early versions of the bill that did not contain § 17, see S. Rep. No. 1175, 67th Cong., 4th Sess., 5 (1923); H. R. Rep. No. 1730, 67th Cong., 4th Sess., 3, 7 (1923), and it was probably considered to be an isolated element in the comprehensive claims settlement procedure established by the Act, rather than a provision of general applicability like § 17. Section 16 was also no doubt designed to encourage the Secretary to take the initiative in urging the Pueblos to consolidate their land holdings after the Board’s work was completed.
  The word “hereafter” in the first clause of § 17 remains a puzzle even under this interpretation. It may be that Congress inadvertently used the word “hereafter” when it intended to say “herein” or “hereinafter”; or perhaps when the word “hereafter” was included in the bill, the subsequent date of enactment might have been regarded as part of the “hereafter.” In any case, this ambiguity in the first clause of § 17 does not alter the clarity of the rule of law established in the second.
  During the Senate Hearings the Chairman of the Subcommittee considering the bills on the Pueblo lands problem referred to the desirability of authorizing the Pueblos to convey their lands with the approval of the Secretary:
  “Senator Lenroot. Have we not general legislation that provides for the alienation of Indian lands with the consent of the Secretary of the Interior?
  “Commissioner Burke. Certainly, as to all Indians, except the Pueblos.
  “Senator Lenroot. They are not included in the statute?
  “Commissioner Burke. No; and no tribal lands can be alienated except by act of Congress. This land is not allotted.
  “Mr. Wilson [representing Pueblos]. There is special legislation covering [the Five Civilized Tribes], and in the Sandoval case the court, in speaking of the tenure to lands of the Pueblo tenants, compared them directly with the tenure of the Five Civilized Tribes. That is patented land, but there was a parallel drawn in the mind of the court, which intended to convey the idea that the Pueblo lands could be handled in precisely the same way as the land of the Five Civilized Tribes.
  “Senator Lenroot. I should like to have you consider whether it might not [be] advisable to provide that these lands may be sold or alienated with the consent of both the Pueblo and the Secretary of the Interior.
  “Mr. Wilson. That is probably going to be quite desirable under some conditions. In fact we have at different times rather encouraged the idea that if they could make swaps and transfers they could get their lands into much better condition. In fact that was the policy at one time that we had with reference to it.
  “Senator Lenroot. Mr Commissioner, would there be any objection to that on the part of the Government.
  “Commissioner Burke. I do not think so. I think there should be authority so that where it was in the interest of the Indians, they might convey, but I would have it under strict supervision of the Department.” Senate Hearings, at 155.
  Sections 16 and 17, authorizing conveyances of Pueblo lands with the approval of the Secretary of the Interior, appeared in later versions of the bill. See also n. 24, supra.
  In 1926, a Special Assistant to the Attorney General offered the same construction of the second clause of § 17 that we adopt today. See App. to Brief for Petitioner 3a-4a. As a result of this construction, the Secretary approved at least 8 other conveyances involving the Pueblo of Santa Ana, between 1926 and 1958, App. 112-115,129-180, and more than 50 involving other Pueblos. Many of the early transactions also involved dismissals from quiet title actions brought by the United States under the Pueblo Lands Act. See Brief for United States as Amicus Curiae 23; supra, at 247-248.
  §§ 1, 3, 43 Stat. 636.
  Edwards’ Lessee v. Darby, 12 Wheat. 206, 210 (1827). See also Zenith Radio Corp. v. United States, 437 U. S. 443, 450-451 (1978); Norwegian Nitrogen Products Co. v. United States, 288 U. S. 294, 315 (1933).