| The mushroom anchor is shaped like an upside-down mushroom and is used widely as a permanent mooring for lightships, dredges, and lighters. |
| The lightships would fire at regular intervals a star shell timed to explode at 6440 feet. |
| The operation lasted 18 months. During that time the area was signalled by 2 lightships and 14 lighted buoys. |
| However within 2 months, British coastal authorities reported 16 ships for having ignored the lightships and buoys. |
| Along the way they took recordings of the sounds of foghorns, lightships, coastguard stations and the voices of those who lived and worked there. |
| New lightships are of similar construction to the older type but are smaller 60 feet or less in length. |
