Nelson Signal Flag Set

Nelson Signal Code – Full set of all signals hoisted during battle of Trafalgar
Each letter of the alphabet was allotted a number, enabling words to be spelled out.
The signaling system in use by the Royal Navy at the time of the Battle of Trafalgar had been introduced in 1799 by Admiral Lord Howe and was further developed by Captain Sir Home Popham. Howe’s original system was based on a set of flags numbered 0 to 9 that when hoisted in various combinations could transmit words, numbers, or messages listed in the Signal Book. Each letter of the alphabet was allotted a number, enabling words to be spelled out, The numeral flags could also be used to send numbers as such. But most signals were two-or three-flag combinations which referenced messages in the Signal Book, e.g. to discontinue the engagement, to pursue the enemy, to anchor, etc. The Signal Book was so arranged that the sender and receiver could quickly compose and interpret flag hoists.
Note: only one hoist would have been shown at any one time during the signal but the set is often used for ceremonial purposes.