The answers to the clues below share an unusual quality.

1. Native of Montevideo
2. Form a line (especially in the eastern US)
3. Far from common
4. Item used in early scientific experiments
5. Guided by strict principles

Answers:

Each answer word contains three U's:

1. URUGUAYAN
2. QUEUE UP
3. UNUSUAL
4. VACUUM TUBE
5. SCRUPULOUS 

Credit: LA Times Crossword
August 13, 2013
Greg Johnson
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