In the course of researching an EXALL known to have served on the destroyer HMS Vesper during the 1920s we examined the Registers of Seamen's Services held at The National Archives, Kew.

• ADM 188 contains two indexes covering admissions to the Royal Navy between 1892 and 1923. We list below all those entering with the surnames EXALL, EXCELL and EXELL. No other variants were found.
  
  
• Service numbers were assigned to show the branch of the service being entered. This was achieved by allocating groups of numbers (1894 - 1907) or with differing alphabetic prefixes (1908 - 1923) as shown in the table below.