Possible Clues:

• Feature of many Cape Cods
• Common Cape Cod feature
• Attic window, sometimes
• Carter at last accessing vault, chamber finally opening
• One is expected to look through it to see reduced sleeping quarters in hospital
• One is expected to see through what's hidden in Ecuador meritocracy
• Window fitted vertically onto a sloping roof
• Window veiled in Ecuador meritocracy
• Window in many loft conversions
• Window fitted vertically onto a sloping roof.