The Spanish government proposed a joint investigation into the disaster, but the United States government declined and conducted a thorough investigation of its own, through a board of eminent official experts. The report was that the loss of the ship was not due to any accident or to any negligence on the part of the officers and crew. The first explosion was external to the hull, as if caused by a torpedo or mine, and it caused the second explosion, which was that of the ship's magazines. The Spanish government then conducted an investigation of its own, resulting in a report that both explosions were within the ship and were presumably purely accidental. It may be added that a final examination in after years, when a cofferdam was built about the hulk and it was floated and then taken out to sea and sunk in deep water, fully confirmed the report of the American investigating board. It is to be recalled that Ramon O. Williams, who had only a little while before retired from the office of American Consul-General at Havana, and was particularly well informed and judicious, earnestly warned the United States government against sending a ship to Havana, because the harbor was very elaborately mined, and there was a bitter and truculent feeling among the Spaniards against the United States; wherefore the danger of some untoward occurrence was too great to be incurred without a more pressing necessity than was then apparent. But despite his warning the _Maine_ was sent. She was conducted by a Spanish official pilot to her anchorage at a buoy between Regla and the old custom house. Whether a mine was attached to that buoy or not is unknown, though Mr. Williams was confident that one was. His theory was that some malignant Spanish officer, who had access to the keyboard of the mines, perhaps through connivance with some other fanatic, watched to see the tide swing the ship directly over the mine and then touched the key and caused the explosion. That would account for the enormous hole which was blown in the side of the ship, and which could not have been caused by any little mine or torpedo which might have been floated to the side of the ship, but must have been produced by a very large mine planted deep beneath the hull. The findings of the American board of investigation were reported officially to the Spanish government, and the President in a message to Congress expressed confidence that Spain would act in the matter according to the dictates of justice, honor and friendship. The Spanish government replied that it would certainly do so, and it presently proposed to submit the whole subject to investigation by impartial experts, and to determination by arbitration. But this proposal was not made until April 10, when so much else had occurred to strain relations between the two countries that it could not be entertained by the United States.