Chief of staff [1]Captain H. V. Butler. Aid and tactical officer Commander B. L. Canaga. Squadron construction and mining officer [1]Comdr. L. F. Kimball. Squadron engineer [1]Lt. Comdr. F. R. Berg. Squadron engineer from 1 October, 1918 [1]Lieut. G. J. Blessing. Flag lieutenant and secretary Lt. Comdr. E. S. R. Brandt. Aid and secretary after 23 August, 1918 Ensign Roger F. Hooper, R.F. Squadron radio officer, also signal officer after 23 August, 1918 Lieut. R. C. Starkey. Communication officer and aid Lt. (j. g.) R. L. White, R.F. Squadron surgeon [1]Lt. Comdr. G. C. Rhoades (M.C.). Squadron surgeon from 1 October, 1918 [1]Lieut. H. P. Stevens (M.C.), R.F. Squadron supply officer [1]Lieut. C. R. Eagle (P.C.). Squadron athletic officer [1]Lt. Comdr. G. W. Hewlett. Assistant squadron construction officer [1]Lieut. G. R. Arey (C.C.). _San Francisco_ (flagship)—Captain H. V. Butler, U.S.N. Launched at Union Iron Works, San Francisco, October 26, 1889, as a protected cruiser; commissioned as a mine ship August 21, 1911; length 324 feet, beam 49 feet, extreme draft 24 feet, full load displacement 4583 tons; twin screw, 18 knots; four 5-inch 51-caliber guns, two 3-inch anti-aircraft guns, 170 mines; officers 22, crew 350; additional for flagship, officers 5, enlisted men 47; total on board 424. _Baltimore_—Captain A. W. Marshall, U.S.N. Launched at Cramp’s Shipyard, Philadelphia, October 26, 1888, as a protected cruiser; commissioned as a mine ship March 8, 1915; length 335 feet, beam 48½ feet, extreme draft 24 feet, 5482 tons; twin screw, 18 knots; four 5-inch 51-caliber guns, two 3-inch anti-aircraft guns, 180 mines; officers 21, crew 339; total 360. _Roanoke_—Captain C. D. Stearns, U.S.N. Launched August 30, 1911, named _El Dia_; commissioned as a minelayer January 25, 1918, at Tietjen and Lang’s Shipyard, Hoboken, N.J. _Housatonic_—Captain J. W. Greenslade, U.S.N. Launched November 14, 1899, named _El Rio_; commissioned January 25, 1918, at Tietjen and Lang’s. _Canandaigua_—Captain W. H. Reynolds, U.S.N. Launched in May, 1901, named _El Siglo_; commissioned March 2, 1918, at the Morse Dry Dock and Repair Company, Brooklyn, N.Y. _Canonicus_—Captain T. L. Johnson, U.S.N. Launched November 14, 1899, named _El Cid_; commissioned March 2, 1918, at the Morse Yard.