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Naval History and Heritage Command

Naval History and Heritage Command

Vice Admiral William S. Sims, Commander, United States Naval Forces Operating in European Waters, to the Office of the Chief of Naval Operations

Subject Copy.                               File No. <16-5-7>

Cablegram Sent May 20 <21> 1918.  RLM.

To Opnav, Washington.                       Serial No. 8198

Prep. by N-3                      SX   D.R.

                                        33 ADR

CONFIDENTIAL

8198. Following being sent by Admiralty to its intelligence centers Quote Warn all ships crossing North Atlantic that large enemy submarines may be encountered west of 40 degrees west and on American Coast.1 Use otters2 when in 90 fathoms or less. Masthead lookouts to be stationed during daylight when north of 15 degrees N. Unquote. <00221> 8198

Sims.             

Source Note: Cy, DNA, RG 45, Entry 517B.

Footnote 1: For more German U-boats operating near the American coast, see: Sims to Opnav, 15 May 1918.

Footnote 2: Otter boards were used to spread out and direct mine sweeping nets. See: Sims to Daniels, 11 April 1918.

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