Vice Admiral William S. Sims, Commander, United States Naval Forces Operating in European Waters, to the Office of the Chief of Naval Operations
File No. 11-2-7
CABLEGRAM SENT March 5, 1918. TCH
To Opnav Washington. Serial No. 4730
Prep. By C-1 SX D.R.
4730. Your 3223. Limit can be extended sixty miles farther north if desired. No other changes recommended. Proposed routing is believed to be safest all things considered. Thus far Admiralty records show no authentic cases of cruiser submarines attacking convoys either by guns or torpedoes. In two or more cases cruiser submarines when sighted by convoy submerged on being pursued by ocean escort. In another case cruiser submarines on approach of convoy prepared to sink ship that he was looting. Thus far cruiser submarine has avoided convoys attacked single vessels at sea with guns only. Orders have been given for westbound ships to remain in convoy until beyond waters where cruiser submarines are operating. 18405
Source Note: Cy, DNA, RG 45, Entry 517B. Additional identification numbers “3/H” appear below the file number in columnar fashion.