The Declaration of London,[1] drawn up in 1909, was an attempt to restate and secure general acceptance of these principles, with notable modifications. Lists were drawn up of _absolute_ contraband (munitions, etc., adapted obviously if not exclusively for use in war), _conditional_ contraband (including foodstuffs, clothing, rolling stock, etc., susceptible of use in war but having non-warlike uses as well), and free goods (including raw cotton and wool, hides, and ores). The most significant provision of the Declaration was that the doctrine of _continuous voyage_ should apply only to absolute contraband. This doctrine, established by Great Britain in the French wars and expanded by the United States in the American Civil War, holds that the ultimate enemy destination of a cargo determines its character, regardless of transshipment in a neutral port and subsequent carriage by sea or land. The Declaration of London was never ratified by Great Britain, and was observed for only a brief period in the first months of the war. Had it been ratified and observed, Germany would have been free to import all necessary supplies, other than munitions, through neutral states on her frontiers. [Footnote 1: Printed in full in INTERNATIONAL LAW TOPICS of the U. S. Naval War College, 1910, p. 169 ff.] _The Blockade of Germany_ Unable to establish a close blockade, and not venturing at once to advance the idea of a "long range" blockade, England was nevertheless able to impose severe restrictions upon Germany by extending the lists of contraband, applying the doctrine of continuous voyage to both absolute and conditional contraband, and throwing upon the owners of cargoes the burden of proof as to destination. Cotton still for a time entered Germany, and some exports were permitted. But on March 1, 1915, in retaliation for Germany's declaration of a "war area" around the British Isles, Great Britain asserted her purpose to establish what amounted to a complete embargo on German trade, holding herself free, in the words of Premier Asquith, "to detain and take into port ships carrying goods of presumed enemy destination, ownership, or origin." In a note of protest on March 30, the United States virtually recognized the legitimacy of a long-range blockade--an innovation of seemingly wide possibilities--and confined its objections to British interference with lawful trade between neutrals, amounting in effect to a blockade of neutral ports.