Dewey gives Gridley discretion over the opening shot

Dewey's order to fire when ready left the immediate timing to Gridley. The wording fits a naval tradition that expected captains to exercise judgment within an admiral's intention. The expectation was to begin shooting when the first volley had a good chance of hitting. Olympia targeted the Spanish flagship, Reina Cristina, and Lieutenant Stokely Morgan fired the opening eight-inch shell. American accounts often credited it with a hit, while Spanish accounts were less certain, leaving the dramatic first-shot success in doubt.