Devonport (Plymouth) Tidal Curve - A4.
Side one shows the curve.
Side two has the time and height differences for seconadary ports from St Mary's (Isle of Scilly) to Exmouth.
It is encapsulated with a matt finish enabling the use of a 2B pencil.
Easier to use than the page from an almanac as the encapsulated curve is far larger and it stays flat.