Thanks for your reply. My grandfather Adam Calder was born while James Charles Thwaites (9years old) was living with my great grand parents. My grandfather was apprenticed to his father in 1878 when JCT was 23. His uncle or other Shetland seaman then living in Sunderland will probably have helped JCT get his first berth on a ship but I doubt he was apprenticed to his uncle who only gained his master's certificate in 1869.
If you know JCT's Master's Certificate Number, it may be possible to view his application at the NMM Greenwich. He would have had to include a list of previous vessels enabling you to trace his travels.
My grandfather's papers are actually made out in his older sister's birthdate! The National Archives Kew hold the papers for my great grandfather's ship for 1878-79. While my grandfather was actually 14 & 15, consular papers stamped at Ferrol (Spain) & Cronstadt (St Petersberg)show that he went from 15 to 17 in 6 months!
Records at Kew also show my grandfather was master of the Ludworth and made several passages through the Dover holding area in 1916 & 17 when his cousin JCT was a pilot.
His sister Jermima's will named 19 beneficiaries including two of your grandfather's sons. She died in 1925 and the bank were still trying to find everyone in 1933 to close the account. Meanwhile I hope they didn't borrow in anticipation as they only got about £15 each!
Peter C Atkinson (Kay's husband)