In vain Russia protested that her partial mobilization was merely a precaution. In vain did the Czar himself offer to give his word that no use would be made of any of his forces. Germany was aware, as subsequent facts have proved, that her own state of mobilization was very much further advanced than that of Russia. GERMAN ULTIMATUM TO RUSSIA By Friday, July 31, Germany was ready for the fray and a final ultimatum to St. Petersburg was launched. On the same day Russia declared war against Austria. By six o'clock on Saturday evening, August 1, war between Germany and Russia began, when Germany dismissed the Russian Ambassador, and by Sunday morning Germany was invading France. The next day, August 3, the German Ambassador left Paris and the French Ambassador at Berlin was ordered to demand his passports. At this point Great Britain passed from the position of general peacemaker to that of a principal. In the House of Commons on Monday, August 3, Sir Edward Grey stated that the question whether Austria or Russia should dominate the Southern Slav races was no concern of England, nor was she bound by any secret alliance to France. She was absolutely free to choose her course with regard to the crisis which had overtaken her. But there were two cardinal points in the situation which had arisen which ultimately concerned Great Britain. The first essential feature of British diplomacy, said Sir Edward, was that France should not be brought into such a condition in Europe that she became a species of vassal state to Germany. On the morning of July 31, therefore, he had informed the German Ambassador that if the efforts to maintain peace failed and France became involved Great Britain would be drawn into the conflict. In his speech of August 3 the British foreign minister also stated that he had given France on the previous day the written assurance that if the German fleet came into the English Channel or through the North Sea to assail her, the British fleet would protect her to the uttermost. TO PROTECT BELGIAN AUTONOMY On the same afternoon, in the same place, Sir Edward Grey reiterated the other dominant principle of British foreign policy--that England can never look with indifference on the seizure by a great continental power of any portion of Belgium and Holland. More than a hundred years ago it was declared by Napoleon, who was a master of political geography, that Antwerp was "a pistol leveled at the head of London."