Keepers of lighthouses and depots wear uniforms similar to those for Masters of lightships, except that no braid is worn on the sleeves and the ratings are shown by the letter “K” or numbers on the collar, while Watchmen wear the letter “W” and a Police shield, as shown in the illustrations. The regulation buttons for the Lighthouse service are gilt and have a design consisting of a lighthouse surrounded by a circle of rope. UNIFORMS AND INSIGNIA OF THE U. S. COAST AND GEODETIC SURVEY Whenever in his judgment a national emergency requires it the President may transfer the ships and personnel of the U. S. Coast and Geodetic Survey from the Department of Commerce to the War Department or Navy Department. When so transferred the commissioned officers take relative rank as follows: Grade 1. Hydrographic and Geodetic Engineers with and after Colonels in the Army and Captains in the Navy. Grade 2. Hydrographic and Geodetic Engineers with and after Lieutenant Colonels in the Army and Commanders in the Navy. Grade 3. Hydrographic and Geodetic Engineers with and after Majors in the Army and Lieutenant Commanders in the Navy. Grade 4. Hydrographic and Geodetic Engineers with and after Captains in the Army and Lieutenants in the Navy. Grade 5. Junior Hydrographic and Geodetic Engineers with and after First Lieutenants in the Army and Lieutenants Junior Grade in the Navy. Grade 6. Aides with and after Second Lieutenants in the Army and Ensigns in the Navy. [Illustration: CAP INSIGNIA COMMISSIONED OFFICERS GRADE 1 GRADE 2-SILVER GRADE 4 GRADE 5 GRADE 6 GRADE 3-GOLD OTHER OFFICERS GOLD LACE STRIPES WITH COLORED DECK VELVET PIPING. OFFICERS COMMISSIONED OFFICERS SLEEVE STRIPES GRADE 1 GRADE 2 GRADE 3 GRADE 4 GRADE 5 GRADE 6 U. S. Coast and Geodetic Survey Officers’ insignia on caps, shoulder straps and coat sleeves] [Illustration: U. S. Coast and Geodetic Survey Officers’ collar insignia, showing branch of the service] Chief Engineers, surgeons, watch officers, mates and deck officers have relative rank with and after commissioned officers of the same rates of pay and when transferred they are given commissions in the Army Reserve or Naval Reserve Force according to their qualifications. All officers are required to have blue service dress, white service dress and field uniforms and an overcoat.