The responsibility for this calamity has never been positively determined. It may have resulted from an accidental internal explosion, from the official action of the Spanish authorities, from the unofficial zeal of subordinate Spanish officers, or even--as suggested by Speaker Reed who was an opponent of war--by action of the insurgents themselves with the purpose of embroiling the United States and Spain. The careful investigations which were afterwards made brought to light evidence of both internal and external explosions; it therefore seems probable that an external mine was the prime cause of the disaster and that the internal explosion followed as a consequence. No direct evidence has been discovered which would fix the responsibility for the placing of the mine, but it is reasonable to attribute it to the Spanish hotheads of Havana. It is not impossible that the insurgents were responsible; but it is incredible that the Spanish Government planned the explosion. The hasty, though perhaps natural, conclusion to which American public sentiment at once leaped, however, was that the disaster was the work of Spain, without making any discrimination between the Government itself and the disaffected factions. A general sorrow and anger throughout the United States reinforced the popular anxiety for national interests and the humane regard for the Cubans. Press and public oratory demanded official action. "Remember the Maine!" was an admonition which everywhere met the eye and ear. The venerable and trusted Senator Proctor, who visited Cuba, came back with the report that conditions on the island were intolerable. On the 9th of March, "Uncle Joe" Cannon, the watchdog of the Treasury, introduced a bill appropriating fifty million dollars to be used for national defense at the discretion of the President. No doubt remained in the public mind that war would result unless the withdrawal of Spanish authority from Cuba could be arranged peaceably and immediately.