delivered the opinion .of the court.

It is well settled that in the courts of the United States the special facts necessary for jurisdiction must in some form appear in the record of every suit, and that the right of removal from the State courts to the United States courts is statutory. A suit commenced in a State court must remain there until cause is shown under some act of Congress for its transfer. The record in the State court, which includes the petition for removal, should be in such a condition when the removal takes place as to show jurisdiction in the court to which it goes. If it is ñot, and the omission is not afterwards supplied, the suit must be remanded'.

The attempt to transfer this cause was made under that part of sect. 2 of the act of 1875 which provides for the removal of suits “ arising under the Constitution or laws of the United. States." In the language of Chief Justice Marshall, a case “ may truly be said to arise under the Constitution or a law of the United States whenever its correct decision depends upon the construction of either ” ( Cohens v. Virginia, 6 Wheat. 379); or when “ the title or right set up by the party may be defeated by one construction of the Constitution or law of the United' States, or sustained by the opposite construction ” (Osborne v. Bank of the United States, 9 id. 822).

The question of jurisdiction was submitted to the Circuit Court, upon the record sent from the State court. Upon the[*202] pleadings alone, it is clear the defendants - had not brought themselves within the statute. The complaint simply set forth the ownership by Keyes of his property, and the acts of the'de-fendants which, it was claimed, created a private nuisance. -No rights were asserted under the Constitution or laws of the United States, and nothing was stated from which it could in any manner be inferredthat the defendants sought to justify the acts complained of by reason of any such.authority. The defendants, in their demurrer, which set forth specifically the grounds relied upon, presented no question of Federal law. The validity of the judgment of the Circuit Court, therefore, depends upon the sufficiency of the facts set forth in the.petition for removal.

For the purposes of the transfer of a- -cause, the petition for removal, which the statute requires, performs the office of pleading. Upon its statements; in connection with the other parts of the record, the courts mitet act in 'declaring the law upon - the question it presents. It should, therefore, set forth the essential facts, not otherwise appearing in the case, which the law has made conditions precedent to the change of jurisdiction. If it fails in this, it is defective in substance, and must be treated accordingly. Thus, in Insurance Company v. Pechner (95 U. S. 183), we decided that a petition for removal, oh account of the citizenship of the parties, did not divest the State court of its power to proceed; because, when taken in connection with the pleadings and process in the cause, it failed to show such citizenship at the time of the commencement of the action as would give the Circuit Court jurisdiction. And in Amory v. Amory (id. 186) we held to-the same effect in reference to a petition which failed to set forth the personal citizen-, ship of the parties.-

The office of pleading is to-state facts, not conclusions of law. It is the duty of the court to declare the conclusions, and of the parties to state the premises.

In this petition, the defendants set forth their ownership, by title derived under the laws of the" United States, of certain valuable, mines that can only be worked by the hydraulic process,-. which necessarily requires the use of the channels of the river and .its tributaries in -the manner complained of; and they allege that they claim th$ right to this use under the provisions[*203] of certain specified acts of Congress; They also allege that the action arises under, and that its determination will necessarily, involve and require the' construction of, the laws of the United States specifically'enumerated, as well as the pre-emption laws, i They state no facts to- show the right they claim, or to enable the court to see whether it necessarily depends upon the construction of the statutes.

Certainly, 'an answer or plea, containing only the statements of the petition, would not be sufficient for the presentation of a defence to the action' under the provisions of the statutes relied, upon. The1 immunities of the statutes are, in effect, conclusions of law from the existence of particular facts. Protection is not afforded to all under all circumstances. In pleading the statute, therefore, the facts must be stated which call it into operation. The averment that it is in operation will not be enough;'for that is the precise question the court is'called upon, to determine.

The statutes referred to contain many provisions; but the particular provision relied upon is nowhere indicated. Á cause cannot be removed from a State court simply because, in the progress of the litigation, it may become necessary to give a construction to the Constitution or laws of the United States. The decision of the case must depend upon that construction. The suit must, in part at least, arise out of a controversy be-' tween the parties in regard to the operation and effect of the Constitution or laws upon the facts involved. That this was the intention of Congress is apparent, from sect; 5 of the act of 1875, which requires the Circuit Court to'dismiss the cause, or remand it to the State court, if .it shall- appear, “ at any time after such suit has been brought or removed thereto, that such suit does not really or substantially involve a dispute or controversy properly within the jurisdiction of said Circuit .Court'”

Before, therefore, a circuit court can be required to retain a cause under this jurisdiction, it'must in some form appear upon the record, by a: statement of facts, “ in legal and logical form,” such as is required in good pleading (1 Chit. Pl. 213), that the suit is one which “ really and substantially involves a dispute or controversy ” as to a right which depends upon the con[*204] struction or effect of the Constitution, or some law Or treaty of the United States. If these facts sufficiently appear in the pleadings, the petition for removal need not restate them; but, if they do not, the omission must be supplied in some form, either by the petition or otherwise. Under the application of this rule, we think that the record in this case is insufficient, and that the Circuit Court did not err in remanding the cause.

The act of 1875 has made some radical changes in the law regulating removals. Important questions of practice are likely to arise under it, which, until the statute has been longer in operation, it will not be easy to decide in advance, For the present, therefore, we think it best to confine ourselves to the determination of the precise question presented in any particular case, and not to anticipate any that may arise in the future. Under these circumstances, the present case is not to be considered as conclusive upon any question except the one directly involved and decided.

Judgment affirmed.