Possible Clues:

• What one can't do to the Thames but perhaps might do for a stream in Scotland
• If you can't set the Thames on fire, you might have more success with this
• Freezer damage?
• Go up in flames; stream
• Can't set the Thames on fire, but might have more luck with this
• Overdo tanning
• Scorch; brook
• Last of flour in roll to be consumed
• Beachgoer's woe
• Set ablaze