CUNNINGHAM v. BROWNING.—1 BLAND. 285

* But those officers whose duty it is, thus carefully to ex-
amine and consider the nature of the proposed grant, before 304
they pass it, cauuot be presumed to know any thing more of it
than what appears upon its face, or than what is represented to
them by the applicant; and yet there may be a variety of circum-
stances, not so apparent, or disclosed, which, if made known,
would clearly demonstrate the great impropriety and injustice of
passing it. Hence, in all such cases, where the interests of a third
person are likely to be materially affected by the granting of a
patent, its emanation may be opposed by such third person; for,
when the immediate possession of land is granted to two several
persons, it begets suits ami troubles, which the common law will
not suffer in the king's grants under the great seal. The Case of
Alton Woods, 1 Co. 50. And therefore, to prevent such mischief,
it is said, that there are three several stages at which the making
out of a patent may be opposed; first, when it is under the con-
sideration of the king: secondly, when it comes to the privy seal;
and thirdly, by a caveat when it comes to the great seal. 1 Mad.
Chart. 18; 1 Chal. Opin. Em. Law, 55. This last appears to be the
most formal and usual course.

In putting the great seal to a patent the Chancellor acts in his
legal capacity; and therefore, in hearing and deciding upon any
controversy which may arise, as to the propriety of passing a pat-
ent, he sits as a Court of common law. 3 Blac. Corn. 49. And so
long as an application thus stands before the Chancellor for the
great seal, he may indulge the parties with farther time upon such
terms as he may deem equitable and proper; but after the great
seal has been once put to the patent, then all further control over
it by the Chancellor in a summary way on a caveat ceases. Ex
patie Beck, 1 Bro. C. C. 578; Ex parte Koops, 6 Ves. 599.

A caveat in Chancery is a petition or suggestion entered by the
party, who supposes himself likely to be injured by the granting
of a patent, respectfully cautioning the Chancellor not to put the
great seal to the instrument until the applicant has been called
upon to make out a proper case for his patent; and also to shew
cause, if any he has, why the objections thus made to its being
granted should not be allowed. Upon which a day is appointed
for the hearing, of which the applicant is notified; and in the in-
terval the parties are allowed, if required, to take testimony in re-
lation to any controverted facts. And at the hearing, the appli-
cant for the patent, considered as a plaintiff, or as holding the
affirmative of the * matter thus put in issue, is allowed to
open and conclude the argument. After which the Chan- 305
cellor may overrule, or allow the objections; from wrhich there is
no appeal: but no costs are given if the caveat be not unreasona-
ble. Ex parte Fox, 1 Fes. & Bea. 67. If the objections are over-
ruled the caveat is discharged, and the great seal is at once put to