Vice Admiral William S. Sims, Commander, United States Naval Forces Operating in European Waters, to the Office of the Chief of Naval Operations
CABLEGRAM SENT April 10, 1918. SFM
To Opnav, Washington Ser. No. 6314
Prep. by CS NCT
6314. Your 4487. My 6151. Madeira appears to offer no facilities as a base for submarines. In the Cape Verde Islands harbors are poor, but probably Porto Grande would be best place. It is not regarded as feasible to base submarines in a locality where there is no secure harbor, as is the case at Madeira and Cape Verde Islands. It is suggested that Department consider basing submarines at Dakar where excellent base facilities belonging to French already exist. I am not convinced that submarines based at any one of the three places mentioned would be better employed than on the home coast where defensive operations may be required against cruising submarines. 6314.
Source Note: Cy, DNA, RG 45, Entry 517B.