SEC. 26. And be it further enacted, That in all causes brought before either of the courts of the United States to recover the forfeiture annexed to any articles of agreement, covenant, bond, or other speciality, where the forfeiture, breach or non-performance shall appear, by the default or confession of the defendant, or upon demurrer, the court before whom the action is, shall render judgment therein for the plaintiff to recover so much as is due according to equity. And when the sum for which judgment should be rendered is uncertain, the same shall, if either of the parties request it, be assessed by a jury.