parliaments, by individual sovereigns, and even by congressional
assemblies of the ministers of European powers, to create new
universal laws, have been declared by these courts to be invalid, and
of no authority. And though it is distinctly laid down, that the Law
of Nations forms a part of the Common Law of England, yet it is not
subject to change by Act of Parliament, as other portions of the
Common Law are; except so far as Parliament can change the form,
constitution, and persons of the courts that declare the law.

Lord Stowell says

"No British Act of Parliament, nor any commission founded
upon it, can affect the rights or interests of foreigners,
unless they are founded upon principles, and impose
regulations, that are consistent with the Law of Nations."

And in another place--

"Much stress has been laid upon the solemn declaration of
the eminent persons (the ministers of the European powers),
assembled in Congress (at Vienna). Great as the reverence
due to such authorities may be, they cannot, I think, be
admitted to have the force of over-ruling the established
course of the general Law of Nations."

It is to the Maritime Courts, then, of this and other countries, that
the hopes of civilization must look for improvement and advance in the
canons of international intercourse during the unhappy time of war.
The manner, and the feeling in which they are to pronounce those
canons cannot be more finely enunciated than in the words of Lord