Possible Clues:

• Indication of highest tide that may be distinctly featured in the paper
• Line on note?
• With a spell on ship's security detail
• Faint feature on a $100 bill
• Feature of banknote: one stolen from attendant, note
• Line showing maximum flood level
• Faint design ends on hot pipe, boarding cosy old ship
• Box below with a handle displaying faint pattern
• Stationery logo
• Label on box of tablets below with a faint pattern