English doctrine of continuous voyage as
advanced during the Napoleonic wars, goods brought from the French West
Indies to the United States and reshipped to continental Europe were
condemned by the British Admiralty Court on the ground that
notwithstanding the unloading and reloading at an American port the
voyage from the West Indies to Europe was in effect a continuous
voyage, and under the Rule of 1756 Great Britain refused to admit the
right of neutral ships to engage in commerce between France and her
colonies. Great Britain, however, seized ships only on the second leg
of the voyage, that is, when bound directly for a belligerent port.
During the American Civil War the United States seized goods under an
extension of the English doctrine on the first leg of the voyage, that
is, while they were in transit from one neutral port to another neutral
port, on the ground that they were to be subsequently shipped in
another vessel to a Confederate port. Great Britain adopted and
applied the American doctrine during the Boer War. The doctrine of
continuous voyage, as applied by the United States and England, was
strongly condemned by most of the continental writers on international
law. The Declaration of London adopted a compromise by providing that
absolute contraband might be seized when bound through third countries,
but that conditional contraband was not liable to capture under such
circumstances. As the Declaration of London was not ratified by the
British Government this distinction was ignored, and conditional as
well as absolute contraband was seized when bound for Germany through
neutral countries.

While Great Britain may be charged with having unwarrantably extended
the application of certain rules of international law and may have
rendered herself liable to pecuniary damages, she displayed in all her
measures a scrupulous regard for human life. Her declaration that "The
whole of the North Sea must be considered a military area," was
explained as an act of retaliation against Germany for having scattered
floating mines on the high seas in the path of British commerce. She
did not undertake to exclude neutral vessels from the North Sea, but
merely notified them that certain areas had been mined and warned them
not to enter without receiving sailing directions from the British
squadron.

The German decree of February 4, 1915, establishing a submarine
blockade or "war zone" around the British Isles, on