Considerable research has been done over the years --thank you, Dobson Family History Group -- into the descendants of Richard Dobson and Margaret Watson, but no one has been able to trace the descendants of their son Joseph Dobson, Sr. (baptised 27 May 1711, Marske-in-Cleveland), who may have married Isabel Agar on 1 January 1736 and did have a son, Joseph Dobson, Jr. (baptised 27 January 1741, Redcar).
Joseph's family makes no further appearances in either the Marske-in-Cleveland or Redcar church records. However, both father and son are still alive as late as 1775, when they are mentioned in the will of Joseph Sr.'s brother, Richard Dobson, Jr. (but no mention is made of where they live at the time).
A promising clue recently surfaced via a Google search.
Extracted from Tyne and Wear Archives Service Catalogue
Title: Records of the Fraternity of Masters and Seamen of Trinity House, Newcastle upon Tyne
Date: 1530 - 1990
Title: Letter from Joseph Dobson, buoy and beacon keeper, Seaton, to Trinity House relating to the dangers of a shoal in the area
Date: 14 Apr 1780
Format: 1 paper
Title: Draught of the entrance to the river Tees by Joseph Dobson, pilot.
Description: Scale: 1 inch to 1 mile. Surveyed January 1762
Format: 1 plan 750mm x 340mm
ADDENDUM: Further description from Tees Renewable Energy Plant ENVIRONMENTAL STATEMENT Volume 1 (PB Power, July 2008):
"Joseph Dobson’s 1762 chart of Teesmouth clearly demonstrates the intertidal nature of the area at the time and is in sufficient detail to be able to gauge the approximate location of the study site [references Figure 14.3, which is not included in the online document]. The coastal settlements at Redcar and Coatham are shown, and other named features are ‘Tod Point’, ‘Dab Holm’ (a low lying point where sloops could moor at low water to allow their cargo to be taken ashore and which gave its name to an estuarine beck that discharged into the Tees), and the port facility at Cargo Fleet. Also much in evidence are the extensive estuarine sand bars, ‘Seal Sand’ and ‘Bran Sand’."
ADDENDUM: Document also kept at North of England Institute of Mining and Mechanical Engineers:
Reference: NRO 3410/Wat/35/3
Creation dates: 1802
Physical characteristics: Scale 1 mile: 1", 50cm x 67cm, printed
Scope and Content: A draught of the entrance to the River Tees, carefully surveyed in January 1762 and most humbly dedicated and presented to the Right Honourable Master, Wardens, Assistants and Elder Brethren of the Corporation Trinity House, at Deptford Strand, surveyed by Joseph Dobson, pilot, sold wholesale, and retail by Christopher and Jennet, Stockton.
Interesting, but not definitively linked to either of my Josephs. Until...according to The History of the Tees Pilots by D.S. Hellier, "Joseph Dobson, who surveyed the River Tees in 1762, is the earliest known Redcar based Tees Pilot."
So the pilot seems likely to either Joseph Sr. or Joseph Jr., but what about the buoy and beacon keeper?
The search continues. Can you help?