The hand salute in the Navy came by way of the British Navy. It is generally agreed that the salute is the first part of the movements of uncovering. That there was nothing in the hand is a possible explanation of the British salute with the palm turned out. From the earliest days of organized military units, the junior has uncovered in addressing or meeting the senior. Lord St. Vincent, in 1796, promulgated an order to the effect that all officers were to take off their hats when receiving orders from superiors.
In 1890, the hand salute only was decreed by Queen Victoria because of her displeasure at seeing officers and men stand uncovered when they appeared for royal commendation.