Signal Letters

There are more than one reason why Bob Scott's query was not answered in the first place. As shall be seen, it will first be necessary to make a rough estimate of the date of the picture and often also to determine the nationality of the ship to be able to correctly decode the signal flags.

However, there is no doubt in my mind that Paul Schopp has not done the correct identification of the ship(s). It cannot be a coincident that the two signals identify two such wellknown ships of the same age and built at the same port. The signal was often reused for a new vessel after a short period of time.

1817 - c1880
Marryat's Code Flags for the Merchant Service. Originally a three digit code which was reorganised and extended to four digits between 1837 and 1841 (possibly for the 7th edition of 1840). No digit was allowed to appear twice in the assigned codes which reduced the maximum number of codes. A distinguishing pendant which could be flown from another mast head, identified it as Marryat's code. To extend the code, additional distiguishing pendants were introduced in 1841, 1860, and 1869. Before the reorganisation, the assignements of codes to new ships had caused duplicates and confusion to be introduced.
c1826 - c1843
Watson's or the Liverpool Code of Signals. A code of no more than three digits which identified the name, nationality and type (rig) of vessel. The top flag was substituted for a pendant when the number of vessels had reached 999. By 1836 ten distinguishing pendants were needed to cover all registered vessels. Watson's code is most confusing as code signals were re-assigned to new vessels all the time.
The Commercial Code of Signals for the Use of All Nations. Only 18 of the letters in the alphabet were used (x, y, z, and the vowels were excluded). The reason for this was to avoid offensive "four" letter words not only in English but in all other languages. With this system the number of possible two and four flag signals amounted to 78.642 of which 50.000 four letter signals were reserved for ships signals. The majority of Marryat's flags were carried over but assigned to the letters of the alphabet.
A revision of the previous system by a joint British-French commission.
S.R. Elson of Calcutta proposed a revidation and extension of the Commercial Code which involved extending the code to 30 flags utilising 15 flags which by turning them upside down doubled the number of signals. This system would extend the number possible signals from 78642 to 546840 (840 with two flags; 21840 with three flags; and 524160 with four flags).
"The New International Code" which was published in 1899 extended the Commercial Code to all letters of the alphabet. The flag for the letter "F" was also changed.
The flags for the letters "C", "D", "E", "F", "G", and "L" were changed in "The 1931 International Code of Signals".
It took some ten years for the Commercial Code to replace Marryat's Code. For instance, Denmark did not adopt the new code until 1869. There is evidence that Marryat's Code was used as late as 1883

The assignement of the inititial letter has been revised serveral times. For instance, Danish ships were originally assigned the series "H" + 3 letters. In 1874 the initial letter was changed to "N" and again in 1931 to "O" in conjunction with revisions of the assignements.

Assignements of signal letters in Great Britain and possibly in most other countries was not obligatory, at least not before 1883. It should also be noted that a vessel's official registration number (introduced in Great Britain with the Merchant Shipping Act of 1854) differed from its signal.

Numerous other systems for identification signals have been proposed or been in use, often locally. In 1855 Reynold's code or "polyglot Nautical Telegraph" was published in an effort to create an international code for universal use. To confuse things this code was using Marryat's Code flags but with a Reynold's Code flag flown from another mast head.

Number flags are e.g. known from the Scandinavian countries, in which the ship's number was displayed often with a code letter for the port of registry in a single flag.

There is no doubt that masters were particular about portraits of their ships, as Trevor Kenchington mentions, however several cases of incorrect hoists have been observed in ship portraits.

In an effort to solve my own queries I went to back to my sources. It seems that the signal letters according to the Commercial Code were included in the "List of Merchant Vessels of the United States" first published by the United States Government in 1868. Although the Commercial Code may have been recognised by Lloyd's Register from the beginning, the signal letters were not published in the Register Book until sometime between 1872 and 1879 [maybe a MARHST-L subscriber could help fixing this date]. The official number of British ships is present in the 1872 register book but not in the 1870 edition.

Although Brewington seems to state that the Roger's American Marine Signal Flags was only used by the United States Navy, there are other evidence that it was also used my the merchant marine.

According to Brewington the dual system was in use in the United States up until 1895.

During the time when several codes were in use a "Code Signal Pendant" was used in conjuction with the signal letters. To make things worse, the Roger's variant of the Commercial Code used the same Code Signal Pendant.


Code Lists

General Works

It is my hope that someone more versed in the art of vexillogy than I continues this important and interesting thread.

Updated 1997-07-22 by Lars Bruzelius

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Copyright © 1996 Lars Bruzelius.