where to hold instrument
Hold the instrument on the small handle vertically and downward - which is part of the outer disk featuring a 365 day date scale.

Hold the instrument on the small handle vertically and downward - which is part of the outer disk featuring a 365 day date scale.
Select the right date by aligning the pointer, part of the inner disk and decorated with a moon face, with the corresponding date on the outside disk.
Now look through the central hole to find the Pole Star, part of the Ursa Minor constellation.
Align the indicator arm with Kochab, a star that is also part of the Ursa Minor constellation and read the aproximate time along the toothed border of the inner disk.
Place the pointer of the middle disk (the moon’s age scale) at 12 o’clock next to the “Fleur-de-Lys” symbol displayed on the outside disc
Move the pointer clockwise to adjust for lunitidal interval correction of your local location. You can simply search for this factor online.
Use the hole on the innermost disc to select the current age of the moon. Then, the indicator arm will show the time of the passage of high tide, the second high tide will be approximately 12.5 hours later.