delivered the opinion of the Court:

We will consider now the assignments of error of the Philadelphia company, the first of which is that the court erred in refusing to direct a verdict for it, “upon the pleadings and all the evidence in the case.” The contention of this defendant is that while the plaintiff’s franchise was the older it was not the superior, and that neither grantee was bound to save the other harmless from the inevitable consequences of the exercise of its privileges or the unavoidable results of interfering with or putting into play the latent forces of nature. It is further con*481tended that there was not sufficient evidence to sustain the aliegation in the declaration of the negligent and unskilful digging of the tunnel.

This tunnel was authorized to be constructed under a public street in the heart of the city, adjacent to the Capitol buildings. The surface of that street was in part lawfully occupied by the plaintiff’s tracks. That the municipal government possesses power to change, grade, or improve this street, without liability to the plaintiff for the unavoidable injury done, is not denied. Kirby v. Citizens’ R. Co. 48 Md. 168, 30 Am. Rep. 455. “But,” as was said by Mr. Justice Van Orsdel in Philadelphia, B. & W. R. Co. v. Karr, 38 App. D. C. 193, L.R.A. —, —, “the case before us presents a very different situation. Defendant owns no interest in the street. The tunnel was not constructed to improve the highway for public use. It was purely a private enterprise for private use and profit. An improvement of a street by the city is the work of the city itself, for the benefit of all its inhabitants, while the use of a street by a railroad company, for the carrying on of its private business, is strictly a private use.” That was an action at law by the owner of a dwelling house abutting on First street for the destruction of the house resulting from the construction of this same tunnel. Negligence in the construction had been alleged, and the case had been tried upon that theory; but in his instruction to the jury the trial judge ignored the question, and ruled that the railroad company was liable for damage resulting proximately from the construction of the tunnel, irrespective of the question of negligence. The action of the trial court was sustained here, this court ruling that under the doctrine of lateral support the existence of negligence was not essential to the right of recovery, the court saying: “If the tunnel had been carefully and prudently constructed, but the damage had occurred to plaintiff’s buildings by reason of the withdrawal of the lateral support in the bed of the street, the case, as to the right- of recovery, would not- be different.”

In the present case the street railway company, while not the owner of property abutting on First street, was the owner of *482tracks and equipment on and under the surface of the street, which had ■ been lawfully placed there. We must also take into account, in determining the intent of Congress, the important fact that the tunnel was to be constructed under this public street over which, in addition to the traffic of the street railway company, traffic of all. kinds was to pass. Any disturbance of the surface of the street, therefore, would not only affect the property of the street railway company, but necessarily would interfere with the public use of the street itself. Having these conditions in mind, we think it clear that Congress did not intend that the grant of authority to construct this tunnel should be exercised irrespective of the rights of the municipality' or of the street railway company. This was expressly ruled in the Karr Case, where it was said: “Congress, as guardian of the rights of the public in the use of the highway, either on the surface or under the surface, did not intend to grant to defendant the right to so construct its tunnel as to impair private rights without compensation. The franchise carried with it the liability; and defendant, in accepting the privilege, accepted liability, which could no more be contracted away than could the franchise itself.” See also Cumberland Teleg. & Teleph. Co. v. United Electric R. Co. 93 Tenn. 492, 27 L.R.A. 236, 29 S. W. 104; Baltimore & P. R. Co. v. Reaney, 42 Md. 117. In reaffirming the view that Congress did not intend such a result, we do not wish to be understood as assenting to the proposition that it possessed power to do so. Baltimore & P. R. Co. v. Fifth Baptist Church, 108 U. S. 317, 27 L. ed. 739, 2 Sup. Ct. Rep. 719; Wight v. Davidson, 181 U. S. 371, 45 L. ed. 900, 21 Sup. Ct. Rep. 616; Richards v. Washington Terminal Co. 233 U. S. 546, 58 L. ed. 1088, L.R.A. 1915A, 887, 34 Sup. Ct. Rep. 654; Baltimore & P. R. Co. v. Reaney, supra.

Here the case was submitted to the jury upon the theory of negligence in the construction of the tunnel, and the verdict, as we have seen, sustained that theory. Under the view above expressed, we do not think the question of-negligence material, and therefore shall not enter upon a discussion of the evidence *483bearing upon that point. Tbe question of negligence not being material, the allegation of negligence and the offer of proof in support thereof did not malee it so. Such was the ruling in the Karr Case. See also Stokes v. Pennsylvania R. Co. 214 Pa. 415, 63 Atl. 1028; Humphries v. Brogden, 12 Q. B. 739, 20 L. J. Q. B. N. S. 10, 15 Jur. 124, 17 Eng. Rul. Cas. 407; Mosier v. Oregon R. & Nav. Co. 39 Or. 256, 87 Am. St. Rep. 652, 64 Pac. 453.

The next assignment of error necessary to be noticed relates to the action of the court in modifying an instruction offered by the defendants, to the effect that if the settlement of the street resulted from the withdrawal of or interference with subterranean or percolating waters beneath the surface of the street, by the excavation for the construction of the tunnel, the plaintiff could not recover, by adding the words, “unless they (the jury) find that said tunnel was constructed negligently, either in the selection of the method of construction or in the execution of such method.” The exception to this modification was general. It now is claimed that “no evidence had been offered by the plaintiff below that the withdrawal of waters could have been stopped by any known system of tunnel construction.” In the first place, the objection was altogether too general. W. T. Walker Furniture Co. v. Dyson, 32 App. D. C. 90, 19 L.R.A.(N.S.) 606. The trial court was entitled to be advised of the specific grounds of the objection. The observance of that rule was especially essential in a case like the present, where such a volume of testimony had been taken. However, we do not think this question at all material. In New York Continental Jewell Filtration Co. v. Jones, 37 App. D. C. 511, 37 L.R.A.(N.S.) 193, it was ruled that there can be no recovery by a landowner for damages to her land caused by excavating for a tunnel under an adjacent public street, where the injury, consisting of a settlement of the land and the cracking of the foundations and walls of a house thereon, was caused by the withdrawal of percolating subsurface water from underneath her premises as the result of the excavation. The difference between that case and this is very clear. “There are no correlative rights existing *484between tbe proprietors of adjoining lands in reference to tbe nse of the water in the earth, or percolating under its surface.” Chatfield v. Wilson, 28 Vt. 49. The grant authorizing the construction of this tunnel did not, as we have ruled, authorize any interference with the surface of the street. It is plain, therefore, that there were correlative rights between those occupying such surface and the grantee of the franchise to construct this tunnel beneath the street. In Humphries v. Brogden, 12 Q. B. 739, 17 Eng. Rul. Cas. 407, already cited, plaintiff was the owner of the surface of the ground and defendant of the right to take the subjacent minerals. Notwithstanding that the jury had found that this right had been exercised carefully and according to the custom of the country, a recovery was permitted for the resulting damage to the owner of the surface. The court said: “Where there are separate freeholds from the surface of the land and the minerals belonging to different owners, we are of opinion that the owner of the surface, while unincumbered by buildings and in its natural state, is entitled to have it supported by the subjacent mineral strata.” In Popplewell v. Hodkinson, L. R. 4 Exch. 248, in which the doctrine was recognized that the owner may drain his own land without liability to his neighbor, the court said: “It may be, indeed, that where one grants land to another for some special purpose, for building purposes for example, then, since according to the old maxim a man cannot derogate from his own grant, the grantor could not do anything whatever with his own land which might have the effect of rendering the land granted less fit for the special purpose in question than it otherwise might have been.” Here there-are two grants from the same source. The senior grantee was occupying the surface of the street under the terms of its grant when the junior grant was made. Can it be that Congress intended to clothe the junior grantee with power directly or indirectly to encroach upon or impair the rights or property of the original grantee ? The terms of the junior grant disclose no such purpose. Why should one public service corporation be injured for the benefit of another ? And yet, if we interpret the statute authorizing the construction of this tunnel as relieving *485the beneficiaries of that grant of liability for any damages incidentally resulting to the holder of the original grant, such must be the result.

The further contention is made by this appellant that it ought not to respond in damages, because the evidence shows that, immediately after the completion of the tunnel, it was turned over to the terminal company, which company has since operated it. So thoroughly is the rule established that he who erects a nuisance continues liable as long as the nuisance continues, that it is unnecessary to dwell upon this contention. Plumer v. Harper, 3 N. H. 88, 14 Am. Dec. 333; Grady v. Wolsner, 46 Ala. 381, 7 Am. Rep. 593; East Jersey Water Co. v. Bigelow, 60 N. J. L. 201, 38 Atl. 631. In the case last cited the court said: “The ground upon which the alienor is held liable for a nuisance created by him is that he is the author of the original wrong, and transferring the premises with the original wrong still existing is treated as affirming the continuance of it.”

We will consider next the assignment of error of the electric railway company. That company complains of the action of the trial court in rejecting its prayer that it be permitted tc recover in this action for all damages, present and future, and in restricting recovery to such damages as had been sustained up to the time of the institution of the suit. This assignment is not seriously insisted upon. We are clearly of opinion that the trial court’s view was correct. In the first place, the company’s license to use the surface of the street may be revoked by Congress, or the company may be required to change the location of its tracks. Then again, unlike the situation in the Karr Case, 38 App. D. C. 193, L.R.A. — , —, it would be impossible at this time accurately to determine the extent of future damage. In addition to these considerations, it is possible that the defects causing the damage may be cured and further trouble averted.

This brings us to the review of the action of the trial court in directing a verdict for the terminal company. That company was incorporated under the act of February 12, 1901 (31 Stat. at L. 774, chap. 354), “for the purpose of constructing *486and owning the terminals, viaducts, railroads, depots, stations, and other works” authorized by the act. Two years later was passed the act (32 Stat. at L. 909, chap. 85G) directing the Philadelphia company or the terminal company, and each of them, to undertake the work authorized by the prior act. In the last paragraph of section 1 of the later act, as previously pointed out, the Philadelphia company was authorized to permit the whole-or a part of the work south of a designated point, including this tunnel, to be solely constructed and owned by the terminal ■ Company, in which event the Philadelphia company was required to purchase one half the capital stock of the terminal company. This right of election was not exercised, although upon the completion of the tunnel it was turned over to the terminal company- the Philadelphia company then having acquired one half of its stock. The agreement entered into at the time between the Philadelphia company, the Baltimore & Ohio Railroad Company, and the terminal company, recited that the “terminal company had under construction and would operate and maintain a railroad and appurtenances,” including this tunnel. It will be observed that no right of election was given the terminal company under said act of 1903, so that unless the Philadelphia company should take advantage of the privilege of election, the construction was to be a joint undertaking. The question is presented, therefore, whether the terminal company, jointly charged by Congress with responsibility for the construction of this.tunnel, which it was to operate and control when completed, and which it did so operate and control under a written agreement reciting that it had participated in the construction and now assumed exclusive control thereof, may escape liability for damages resulting from such construction upon the theory that it did not participate therein. It seems to us that the question answers itself. Neither of the companies jointly interested in the construction of this tunnel could accept the benefits conferred by the statute without incurring the resulting obligations. lust why the Philadelphia company was empowered to act with the terminal company is *487not clear, but it is clear from a reading of this and the earlier act that the terminal company was to take charge of, manage, and control the tunnel when completed. The agreement under which the intent of the statute was carried out, therefore, is merely a recognition of that intent. It would be a startling proposition that the terminal company, the real beneficiary of this construction, could, by disregarding its plain duty, escape responsibility for resulting damages. The time or date of the taking of possession by the terminal company does not measure its responsibility; that was fixed by Congress and attached with the acceptance of the authority granted. We rule that the terminal company was as much responsible for the damages resulting from the construction of the tunnel as was the Philadelphia company.

The judgment against the Philadelphia company is affirmed, with costs. The judgment for the terminal company is reversed, with costs, and the cause remanded.

Affirmed in part and reversed in part.