On bard the Central America, a ship on her way from Havana to New York, were on fewer than 491 passengers. Most of them were miners（矿工）returning with their gold to their homeland. At the start of the voyage, the sky had been cloudless and the wind fair. Three days later, however, the ship was rolling in a storm.

Soon water poured in the engine-room and put out the fires. This left the ship helpless, with her engines stopped. In spite of all efforts, the depth of the water down below slowly increased. It became clear to all that nothing could save the ship, and that she would soon go to the sea bottom.

Just at that moment, a strange sight was seen on bard. Some of the miners collected their gold and stored it in their belts. They hoped to take it with them wherever they were going. But others knew that the ship would sink and didn't want to weigh themselves down with the heavy metal. So they threw it not the floor.

Unusual courage was shown by nearly all on bard. The captain moved about the ship encouraging all. He sometimes gave orders in attempts to save his ship, and sometimes kept silent, always determined. But all his efforts failed.

Fortunately, when all hope had gone, anther ship, the Marie from Boston, appeared on the scene. The Marie had also suffered heavily in the storm, but her captain immediately arranged to move the people in bats from the Central America to his own ship. The huge waves made the work painfully slow, but there was no disorder: everyone waited patiently. Finally, all passengers were saved.

Some miners threw their gold not the floor because they _____.