my.

The offense of trading with the enemy is not a new one in international
law. In 1799 Sir William Scott, afterwards Lord Stowell, sitting upon
the case of the _Hoop_, which is perhaps the leading case upon the
subject, declared that all trading with the enemy by the subjects of one
State without the permission of the sovereign is interdicted in time of
war[1]. It was pointed out that, according to the law of Holland, of
France, of Spain and as a matter of fact of all the States of Europe,
"when one state is at war with another, all the subjects of the one are
considered to be at war with all the subjects of the other and all
intercourse and trade with the enemy is forbidden." This principle has
been accepted in the United States as one of the conditions of warfare.
Wheaton declares: "One of the immediate consequences of the commencement
of hostilities is the interdiction of all commercial intercourse between
the subjects of the States at war without the license of their
respective Governments."[2]

[Footnote 1: 1 C. Rob. 200.]

[Footnote 2: Elements of International Law, Dana Ed. (1866), Sec.309 et
seq.]

In England a declaration of war is equal to an Act of Parliament
prohibiting all intercourse with the enemy except by the license of the
Crown. The penalty of such illegal intercourse is the confiscation of
the cargo and of the ship engaged in such trade. The instructions are
emphatic upon the point: "The commander should detain any British vessel
which he may meet with trading with the enemy unless, either: (1) He is
satisfied that the master was pursuing such trade in ignorance that war
had broken out, or, (2) The vessel is pursuing such trade under a
license from the British Government."[3]

[Footnote 3: British Admiralty Manual of Naval Prize Law (1888), Sec.38.]

When a vessel is bound for a belligerent port it appears that the burden
of proof is thrown upon the ship's captain to show that goods so shipped
are not intended for the enemy. In the case of the _Jonge Pieter_ (1801)
goods purchased in England were shipped for an enemy port but were
seized by a British cruiser under the right of a belligerent. It was
attempted to be set up that the goods belonged to citizens of the United
States, but in the absence of documentary proof condemnation was decreed
on the ground of hostile ownership.[4]

[Footnote 4: 4 C. Rob. 79; other cases bearing upon the subject are: the
_Samuel_ (1802), 4 C. Rob. 284 N; the