Aiguilettes worn by Naval Officers are loops of plaited blue and gold cord terminating in gilt metal ornaments decorated with silver anchors. They are worn by personal aids to the President and the Secretary of the Navy, aides at the White House, members of the personal staff of a Flag Officer in command of a fleet or subdivision of a fleet, and by aides to the Commandants of Naval Stations and the Superintendent of the Naval Academy. The personal aides to the President wear the aiguilettes on the right side and all other officers for whom they are prescribed wear them on the left side. They are worn with all uniforms to indicate the special duty of the wearer as an aide entitled to convey the orders of the officer to whose staff he is assigned. _The Sword knot_ for naval officers is a loop of gold braid ending in a bullion tassel, worn on the hilt of the sword. The original purpose of this loop was to wear it around the right wrist when the sword was carried in the hand to prevent the loss of the sword if it should be accidentally dropped or knocked from the hand in combat. The sword knot is worn by commissioned officers only. _Officers of the Line and of the Staff Corps of the Naval Reserve Force_ wear the same rank marks as those described for the officers of the regular Navy, but, instead of the silver anchor for the Line Officers and the various Corps devices and insignia to indicate the Corps or branch of the service of the Staff officers of the Staff of the regular Navy, they wear the Naval Reserve Force device on the collar of the blue service coat. The Naval Reserve Force Device or insignia is of the same design as the device worn on the front of the cap by commissioned officers of the Navy. It is one inch in height, made of metal, the shield and eagle being of silver and the crossed anchors of gold. The gilt buttons worn by officers of the Naval Reserve Force are of the same sizes as those worn by the officers of the regular service but the design is different, and by this design the fact that an officer is a member of the Naval Reserve Force is shown when he is wearing any uniform having gilt buttons. The Naval Reserve Force gilt button for officers bears a plain vertical anchor and the letters U. S. N. R., as illustrated. UNIFORMS AND INSIGNIA OF MIDSHIPMEN The Corps of Midshipmen at the Naval Academy is organized into a regiment of four battalions of four companies each for military formations and drills, with Midshipmen Officers and Petty Officers, as follows: