The Court first recognized and applied the doctrine "of recognition and acquiescence of a boundary line" in Carstensen, 236 P. at 520-521. The doctrine was invoked to award title to Brown, even though in an earlier opinion in the same case, Carstensen v. Brown, 26 Wyo. 356, 185 P. 567, 569 (1919), the court had ruled that there was not sufficient evidence to support a claim of adverse possession. The result of the second case was described in City of Rock Springs v. Sturm, 39 Wyo. 494, 273 P. 908, 911 (1929), as "diametrically opposite to that reached on the first appeal." In his usual, diligent fashion, Justice Blume examined the doctrine critically and thoroughly. the opinion explained the doctrine of acquiescence and recognition and distinguished it from adverse possession saying: The doctrine of recognition and acquiescence of a boundary line is upheld by many authorities. 9 C. J. 244; Tiffany, Real Property (2d Ed.) 295; Thompson on Real Property, 3112. It is sometimes referred to as acquiescence in, or as a practical location of, or as an implied agreement as to, a boundary. Considering all of the various jurisdictions in the United States, the doctrine is still in a chaotic condition, and no one has yet undertaken to point out definitely the circumstances under which it is applicable. Some of the authorities consider long acquiescence only as evidence of a boundary, which may be contradicted. Tiffany, supra, 295. Other authorities say that an agreement may be inferred or presumed from such acquiescence. Note, 110 A. S. R. 685. the doctrine seems to occupy a middle ground between adverse possession and estoppel in pais. It is frequently held that, in order to work an estoppel by conduct, it is necessary that the party against whom it is claimed should have knowledge of the true boundary (Bigelow on Estoppel 16th Ed. p. 674) and, as said in Carstensen v. Brown, 26 Wyo. 356, 185 P. 567, where both parties are ignorant thereof and have an equal opportunity to know the facts, no estoppel arises. It may be said, however, in this connection, that in many states long acquiescence is accepted as a substitute for knowledge of the facts, and an estoppel may arise in cases of mistake by acquiescence, in connection with a change of situation. Bigelow, supra, p. 675. See Lehman v. Smith, 40 S.D. 556, 168 N.W. 857, where some distinctions between the two doctrines were pointed out. In adverse possession it is requisite, according to the majority of decisions, including Fieldhouse v. Leisburg, 15 Wyo. 207, 88 P. 214, that there be an intent to claim up to a marked division line without reference to where the true line may be, and, if it appears that there was only an intent to hold to the true line, the possession is not adverse, and no title by prescription may be obtained. Note, 15 Ann. Cas. 827; Note Ann. Cas. 1912A, 450; 2 C. J. 139. Indeed, some of the authorities have held that no title by adverse possession can be acquired through a mistake, although in the greater number of cases at least some mistake exists when possession is taken of another's property. Note, 21 L. R. A. 831. Such holding practically results in this, that the intent necessary to make possession adverse is akin to a felonious intent (Ibid), thus virtually making it impossible to gain any prescriptive title. The trend of opinion is said in a note to 33 L. R. A. (N. S.) 930, to be against disturbing a person whose visible boundaries have existed for the period of the statute of limitations. Indeed, some of the authorities have distinctly repudiated the view that it is necessary to claim beyond the true boundary, and that, if a man occupies and claims what he believes to be his own, his possession is adverse and ripens into title upon the expiration of the statutory time. Yetzer v. Thoman, 17 Ohio St. 130, 91 Am. Dec. 122; French v. Pearce, 8 Conn. 439, 21 Am. Dec. 680; Bayhouse v. Urquides, 17 Idaho 286, 105 P. 1066; Notes, 15 Ann. Cas. 829, Ann. Cas. 1912A, 451; Ramsey v. Ogden, 23 Ore. 347, 31 P. 778. It would seem that in Ohio and Indiana the courts treat recognition and acquiescence in a boundary line for a period equal to that of the statute of limitations the same as adverse possession for a like period. Yetzer v. Thoman, supra; Helbling v. Realty Co., 2 Ohio App. 478; Rutledge v. Presbyterian Church, 3 Ohio App. 177; Epstein v. Kraft, 16 Ohio Cir. Ct. (N. S.) 251; Thomas v. Webber, 13 Ohio N. P. (N. S.) 301; Scheigert v. Boyer, 69 Ind. App. 674, 122 N.E. 670; Rosenmeier v. Mahrenholz, 179 Ind. 467, 101 N.E. 721; Dyer v. Eldridge, 136 Ind. 654, 36 N.E. 522. But, according to most of the courts, it is not identical with it, and the two doctrines are treated as distinct. Miller v. Mills County, 111 Iowa 654, 82 N.W. 1038; Morley v. Murphy, 179 Iowa 853, 162 N.W. 63; Hubbard v. Stearns, 86 Ill. 35; Brummell v. Harris, 148 Mo. 430, 440, 50 S.W. 93; Schwartzer v. Gebhardt, 157 Mo. 99, 104, 57 S.W. 782. See Lehman v. Smith, supra. the distinction is pointed out in the last-cited case Schwartzer as follows: "It is well settled that the possession of coterminous proprietors under a mistake or in ignorance of the true line, between them and without intending to claim beyond the true line, will not work a disseisin, and set in motion the statute of limitation in favor of either, but it is equally as well settled that when such proprietors, in ignorance of the true line, fix and agree upon a permanent boundary line, and possession is taken accordingly, the agreement is binding upon them, and those claiming under them. Jacobs v. Moseley, 91 Mo. 457, 4 S.W. 135. Such an agreement is not within the statute of frauds. Taylor v. Zepp, 14 Mo. 482; Blair v. Smith, 16 Mo. 273; Turner v. Baker, 64 Mo. 218; Acton v. Dooley, 74 Mo. 63. Nor is it necessary that such an agreement should be shown by direct evidence, but it may be inferred from the acts and conduct of the parties, and their long acquiescence and recognition of the line established as the true line." Carstensen, 236 P. at 519-20.