For further information on P. L. Robertson, please see "P. L. Inventor of the Robertson Screw" by Ken Lamb and "Milton Area Biographies" by Alex Cooke.
For further information on P. L. Robertson, please see "P. L. Inventor …
This series of photographs was taken during P. L. Robertson's trip to Scotland in August and September 1918. The photographs are pasted into an album with the following inscription "To Stimulate The
This series of photographs was taken during P. L. Robertson's trip to …
This series of photographs was taken during P. L. Robertson's trip to Scotland in August and September 1918. They are pasted into an album with the following inscription "To Stimulate The memory of M
This series of photographs was taken during P. L. Robertson's trip to …