Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Ep. No. | Title | Director | Written by | Original Air Date | Production No. |
| --- | --- | --- | --- | --- | --- |
| 1.0 | "Instrument of Destruction: Part 1" | David Lane | Phil Ford | 12February2005 | 1.0 |
| 2.0 | "Instrument of Destruction: Part 2" | David Lane | Phil Ford | 19February2005 | 2.0 |
| 3.0 | "Swarm" | David Lane | Phil Ford | 26February2005 | 8.0 |
| 4.0 | "Rat Trap" | Dominic Lavery | Phil Ford | 5March2005 | 7.0 |
| 5.0 | "The Homecoming" | David Lane | Phil Ford | 12March2005 | 5.0 |
| 6.0 | "Mercury Falling" | Dominic Lavery | Phil Ford | 19March2005 | 4.0 |
| 7.0 | "Circles of Doom" | Mark Woollard | Brian Finch | 26March2005 | 9.0 |
| 8.0 | "Rain of Terror" | Mark Woollard | John Brown | 9April2005 | 3.0 |
| 9.0 | "Skin Deep" | Mark Woollard | John Brown | 16April2005 | 12.0 |
| 10.0 | "Chiller" | Mark Woollard | Phil Ford | 23April2005 | 6.0 |
| 11.0 | "Trap For a Rhino" | Dominic Lavery | John Brown | 30April2005 | 10.0 |
| 12.0 | "Heist" | Dominic Lavery | Phil Ford | 7May2005 | 13.0 |
Question:
Who wrote the episode called "mercury falling"?
Answer:
Phil Ford