Vice Admiral William S. Sims, Commander, United States Naval Forces Operating in European Waters, to Detachment Commanders in European Waters
Cablegram Sent Nov.10, 1917.
To See Below Serial No. See Below
Via N C B 17 ADR Prep. by EGB Appvd. by COS
Copies to COS, JVB, EGB.
[number obliterated] Ampat Brest.
269 Melvus Queenstown
176 Senafloat Gibraltar
82 Senafloat Ponta del Gada.
<226> Admiralty has issued following instructions Quote Any vessel proceeding in company with British or Allied submarines will fly international flag “M” at mast head, accompanied by a group from the numeral table in the International Code of Signals indicating the number of submarines in company Unquote.
Source Note: Cy, DNA, RG 45, Entry 517B. Identification numbers “1/5/J/N” appear in the upper-right corner.