Colonel William Travis is said to have drawn a line in the sand with his sword and asked his men how many of them were willing to step across it and give their lives for the cause.
Although it is impossible to know exactly where this took place, there is a plaque at The Alamo that commemorates this famous quote, and the line Travis drew in the sand is often referred to as the "Grand Canyon of Texas."
To the People of Texas & All Americans in the World
Fellow citizens & compatriots
I am besieged, by a thousand or more of the Mexicans under Santa Anna I have sustained a continual Bombardment & cannonade for 24 hours & have not lost a man The enemy has demanded a surrender at discretion, otherwise, the garrison are to be put to the sword, if the fort is taken I have answered the demand with a cannon shot, & our flag still waves proudly from the walls I shall never surrender or retreat. Then, I call on you in the name of Liberty, of patriotism & everything dear to the American character, to come to our aid, with all dispatch The enemy is receiving reinforcements daily & will no doubt increase to three or four thousand in four or five days. If this call is neglected, I am determined to sustain myself as long as possible & die like a soldier who never forgets what is due to his own honor & that of his country VICTORY OR DEATH.