Signal Flag Systems

Signal flags are used to visually identify ships and send messages through the use of a published book of codes. The code systems visible in many of the museum paintings however, predate the current International Code of Signals. The accuracy of marine painting often allows vessel identification to be made solely on the basis of the owner flags and signal system depicted on the vessel.

Elfords Flags

Elford's Telegraphic Flags

Until 1857

The Elford Telegraph system was used in Boston Harbor and along the Atlantic Seaboard. The flags are easy to read since blue and white are the only colors.

In this painting of the Packet Liverpool, the Elford flags for 5141 fly on the mizzenmast ( Watson flags are also present - see below ).


Watson's Holyhead to Liverpool Numeric Flags


Watsons Flags
The Holyhead to Liverpool system used three numeric flags with triangular pennant extensions to accommodate a larger number of ships.

The Packet Liverpool carries the Watson codes 784.


Captain Frederick Marryat's Signal Flag Code


Marryats Flags
In the Marryat system a ship was identified by up to four numeric flags preceeded by a distinguishing pennant. Each distinguishing pennant represented a series of ten thousand ships. The Marryat code was superseeded by the International Code of Signals in use today.

The Marryat code 3rd D.P. 3078 is visible in the portait of the Kineo.


The International Code of Signals

1855 to Date

International Flags
First drafted in 1855, this system was first published as an international and a British volume in 1857 and gradually adopted by most seafaring nations. The 1932 revision was published as visual and radiotelegraphy volumes in the English, French, German, Italian, Japanese, and Norwegian languages.


Last Modified November 24, 1996