evision by his writ of error; and also that the defendant waived
this defense by pleading over, and thereby admitted the jurisdiction of
the court.

But in making this objection, we think the peculiar and limited
jurisdiction of courts of the United States has not been adverted to.
This peculiar and limited jurisdiction, has made it necessary, in these
courts, to adopt different rules and principles of pleading, so far as
jurisdiction is concerned, from those which regulate courts of common
law in England, and in the different States of the Union which have
adopted the common-law rules.

In these last-mentioned courts, where their character and rank are
analagous to that of a Circuit Court of the United States; in other
words, where they are what the law terms courts of general jurisdiction;
they are presumed to have jurisdiction, unless the contrary appears. No
averment in the pleadings of the plaintiff is necessary, in order to
give jurisdiction. If the defendant objects to it, he must plead it
specially, and unless the fact on which he relies is found to be true by
a jury, or admitted to be true by the plaintiff, the jurisdiction can
not be disputed in an appellate court.

Now, it is not necessary to inquire whether in courts of that
description a party who pleads over in bar, when a plea to the
jurisdiction has been ruled against him, does or does not waive his
plea; nor whether upon a judgment in his favor on the pleas in bar, and
a writ of error brought by the plaintiff, the question upon the plea in
abatement would be open for revision in the appellate court. Cases that
may have been decided in such courts, or rules that may have been laid
down by common-law pleaders, can have no influence in the decision in
this court. Because, under the Constitution and laws of the United
States, the rules which govern the pleadings in its courts, in questions
of jurisdiction, stand on different principles and are regulated by
different laws.

This difference arises, as we have said, from the peculiar character of
the Government of the United States. For although it is sovereign and
supreme in its appropriate sphere of action, yet it does not possess all
the powers which usually belong to the sovereignty of a nation. Certain
specified powers, enumerated in the Constitution, have been conferred
upon it; and neither the legislative, executive, nor judicial
departments of the Government can lawfully exercise any authority beyo