Braley, J.
The restricted covenants against incumbrances and of warranty contained in the defendant’s deed under which the plaintiffs derived their'title are independent, and a breach of either would give a distinct cause of action. The building and maintaining of a public sewer through a part of the granted premises did not constitute a breach of the first covenant, as the action of the public authorities was neither caused nor permitted by the grantor. Estabrook v. Smith, 6 Gray, 572, 577. West v. Spaulding, 11 Met. 556. Cole v. Lee, 30 Maine, 392, 397. But the covenant of warranty was broken by the constructive eviction caused by its maintenance, if the easement taken by eminent domain is derived from and supported by the title of the defendant. Comstock v. Smith, 13 Pick. 116. Raymond v. Raymond, 10 Cush. 134, 140. Smith v. Richards, 155 Mass. 79, 82. It therefore becomes important to consider whether upon its exercise the public acquired in the land a derivative or an independent title.
*298In Pollard v. Hagan, 3 How. 212, 223, where the right of the Federal Government in the soil of the States carved out of the Louisiana Purchase is considered, Mr. Justice M’Kinley defines this function as follows: “ The right which belongs to the society, or to the sovereign, of disposing, in case of necessity, and for the public safety, of all the wealth contained in the State, is called the eminent domain.” By force of this power, back of all private titles lies the eminent domain as an inherent attribute of organized government: Perry v. Wilson, 7 Mass. 393. Goodyear Shoe Machinery Co. v. Boston Terminal Co. 176 Mass. 115. And whenever the Legislature adjudges it expedient the property of the citizen may be appropriated for public use. The taking may be by legislative act, or the right may be delegated. Talbot v. Hudson, 16 Gray, 417, 424. In re Mayor & Aldermen of Northampton, 158 Mass. 299. Abbott v. New York & New England Railroad, 145 Mass. 450, 453, 454. Commonwealth v. Boston Terminal Co. 185 Mass. 281. Ordinarily where land is condemned for this purpose the quality of the estate is defined either by the paper taking, or its extent may be measured by the object to be accomplished. It may be a fee or an easement. Harback v. Boston, 10 Cush. 295. Page v. O’ Toole, 144 Mass. 303. Titus v. Boston, 161 Mass. 209. Newton v. Perry, 163 Mass. 319, 321. Newton v. Newton, 188 Mass. 226, 228. But whatever the interest appropriated, the owner must be fully compensated. Declaration of Rights, art. 10. Whitman v. Nantucket, 169 Mass. 147, 149. Hellen v. Medford, 188 Mass. 42, 45. This provision of our Constitution, which either by direct enactment or by reference to similar provisions in existing laws is usually embodied in the statute by which the right is exercised or delegated, while an inseparable incident forms no part of the power itself. Boom Co. v. Patterson, 98 U. S. 403, 406. United States v. Jones, 109 U. S. 513, 518. Cooley, Const. Lim. (7th ed.) 813. Dillon, Mun. Corp. § 590. See 1 Thayer, Cas. Const. Law, 953, note. Nor does the right to compensation affect the validity of the condemnation where the landowner either assents, or allows his claim to be barred by limitation. Haskell v. New Bedford, 108 Mass. 208, 214.
If -the State takes property by escheat or forfeiture it sue*299ceeds to the title of the former owner, and claims under him. 4 Kent Com. (14th ed.) 427, note b. Casey v. Inloes, 1 Gill, 430. Colgan v. McKeon, 4 Zabr. 566, 575. And this is so when an execution is levied by sale of real estate. The purchaser by operation of law gets the debtor’s title, and nothing more, and it follows that if the wife purchases under the sheriff’s deed she acquires no title, which then remains in the husband, as in contemplation of law the deed is a mere conveyance from her husband to herself. Stetson v. O’Sullivan, 8 Allen, 321. In the foreclosure of a mortgage or under an assignment in bankruptcy a purchaser at the sale or the assignee can get no greater estate than the mortgagor conveyed or the bankrupt owned. These familiar instances are illustrative of derivative titles where those who purchase take" by grant or succeed by assignment, and acquire no greater interest than that held by those under whom they claim.
But if the principle is applicable to real property seized in the exercise of the right of eminent domain, then if only a bare title is taken, which later is found to be invalid because a mistake has been made in ascertaining thé ownership, the condemnation must be repeated, or the public can be ousted by the true owner. Goodyear Shoe Machinery Co. v. Boston Terminal Co., ubi supra. The language used by this court when discussing the nature of the proceedings indicates more than a transfer of an existing title. Thus it was said in Brown v. Lowell, 8 Met. 172, 178, when speaking of the adjudication of the mayor and aider-men in laying out a way over private property, “ the latter appropriates the land to the public, and divests the right ofr the owner to the exclusive use and possession of it, from the time it is passed.” See also Commonwealth v. Boston & Lowell Railroad, 12 Cush. 254, 258; Drury v. Boston, 101 Mass. 439, 440; Monongahela Navigation Co. v. United States, 148 U. S. 312, 324. The probability of such an interference if a mistake has been made in the identity of the owner or owners is repugnant to the nature and scope of the right itself. To avoid such complications and to make the right immediately effective the appropriation of private property for a public use is strictly a proceeding in rem, and has been so defined by our decisions. Edmands v. Boston, 108 Mass. 535, 544. Appleton v. Newton, 178 Mass. 276, *300281. Lancy v. Boston, 185 Mass. 219. Sweet v. Boston, 186 Mass. 79. The power when exercised acts upon the land itself, not upon the title, or the sum of the titles if there are diversified interests. Upon appropriation all inconsistent proprietary rights are divested, and not only privies but strangers are concluded. Clark v. Worcester, 125 Mass. 226, 231. Brigham v. Fayerweather, 140 Mass. 411, 413. See also The Avon, Brown, Adm. 170; Certain Logs of Mahogany, 2 Sumner, 589. Thereafter whoever may have been the owner, or whatever may have been the quality of his estate, he is entitled to full compensation according to his interest and the extent of the taking, but the paramount right is in the public, not as claiming under him by a statutory grant, but by an independent title. Boston Water Power Co. v. Boston & Worcester Railroad, 23 Pick. 360, 393, 394. Dingley v. Boston, 100 Mass. 544, 559. Emery v. Boston Terminal Co. 178 Mass. 172, 184. Beekman v. Saratoga & Schenectady Railroad, 3 Paige, 45, 73. Todd v. Austin, 34 Conn. 78. Harding v. Goodlett, 3 Yerger, 41, 53. Weir v. St. Paul, Stillwater & Taylor's Falls Railroad, 18 Minn. 155. West River Bridge Co. v. Dix, 6 How. 507. See also League v. Texas, 184 U. S. 156; Long Island Water Supply Co. v. Brooklyn, 166 U. S. 685.
This conclusion is further supported by the analogy of the sale of land for unpaid taxes where the purchaser, which may be the city or town, gets a new unincumbered title in fee by force of the lien of the taxing power, which cuts under all incumbrances or qualifying estates. R. L. c. 13, § 48. Harrison v. Dolan, 172 Mass. 395, 398. Emery v. Boston Terminal Co. 178 Mass. 172, 184. Hunt v. Boston, 183 Mass. 303, 306. Abbott v. Frost, 185 Mass. 398, 400. Hefner v. Northwestern Ins. Co. 123 U. S. 747, 751. Textor v. Shipley, 86 Md. 424, 438. McQuity v. Doudna, 101 Iowa, 144, 146. Independently of the theory of compensation for a compulsory surrender of his land by the citizen as distinguished from the equal benefit which the taxpayer gets as the equivalent of his tax, this power of organized government to levy a proportional tax for the purpose of raising public revenue is no more essential than the power, if necessity requires its exercise, to appropriate private property for a public use. If in one case *301there is a new grant under the seizure which conveys the land as such without regard to old titles, there is no satisfactory reason why a taking under eminent domain is not of a similar nature. Indeed, the grant to the purchaser at the tax sale and the taking under eminent domain are alike to supply governmental needs. By one process it takes and conveys to pay the •tax; by the other it takes and retains for its own use. In each instance the tenure is original and independent. Goodyear Shoe Machinery Co. v. Boston Terminal Co., Emery v. Boston Terminal Co., Dingley v. Boston, West River Bridge Co. v. Dix, ubi supra. The case of Burt v. Merchants' Ins. Co. 106 Mass. 356, is not in conflict. The construction of the St. of 1870, c. 327, by which the Commonwealth gave its consent that the United States might condemn land as a site for a post office in'the city of Boston was the question presented for decision. This act provided that if the owners of the estates to be acquired could not agree upon the price, then an application might be made to the Superior Court to have the valuation fixed by a jury. The owners not having agreed a petition was brought, and, no proof being offered of any agreement between the parties for a purchase and sale, the question was whether the petition could be maintained. It was held that the word “purchase” was broad enough to include a taking by the delegated right of eminent domain. But this is far from saying that by the exercise of this right the public acquire nothing more than a derivative title. The language used that “ the property is held under a statute conveyance, and the title is in legal phrase by purchase ” is to be read in connection with the provision found in the last part of the second section that after a jury has ascertained the value, then upon tender of this sum with costs and expenses, or if the respondent refuses to accept, upon deposit of this amount for its use with the treasurer of the Commonwealth, the fee should vest in the United States. It is manifest that nothing more was meant than to say that by intendment of law title by purchase includes all title to real property except when acquired by descent, and this was the construction of similar language in Kohl v. United States, 91 U. S. 367, where it was held that while the words “ to purchase ” might be considered as including the power to acquire by condemnation, yet generally *302in statutes as well as by common use the word “ purchase ” is employed to denote acquisition by contract between the parties without governmental interference.
In the opinion of a majority of the court, the city of Boston not having acquired an easement “by, through or under” the defendant his covenant of warranty was not broken, and the ruling asked for in the defendant’s first request should have been given. West v. Spaulding, ubi supra.
Exceptions sustained.