Related Clues:

• Tends to a squeak
• Some are essential
• Rembrandt's medium
• Greases
• Reduces friction, in a way
• Met works
• Bathwater additives
• Artist's medium
• Manet medium
• Some Louvre attractions
• Artist's media, perhaps
• Classical paintings
• "Luncheon on the Grass" and "Haystacks," e.g.
• Certain paintings
• Treats squeaks