PERIODICTABLE
| Date | Clue |
|---|---|
| 2018-08-08 | *Dmitri Ivanovich Mendeleev and Julius Lothar Meyer |
| 2009-05-08 | Science class decoration |
| 2008-09-30 | Chemistry class poster, perhaps |
| 2006-03-24 | Place for I, O or U |
| 2004-11-18 | Occasional furniture? |
| 2000-06-28 | It begins with H |