Leading lights
From Arthur Ransome Wiki
Leading lights or Leading marks are a navigation aid used to indicate a safe passage through a hazardous passage when the hazards may not be visible. They are most often found at harbour entrances and consist of two marks which are usually lit at night.
The marks are placed at different heights along the line of the safe course but separated by some distance so that if you stray off the correct course, parallax will make the marks no longer appear vertically one above the other.
In Swallows and Amazons leading marks were used by the Amazons to allow them to enter Wild Cat Island's Secret Harbour quickly and easily, but John explained to them what they were called (SA11). John also had the idea of attaching lights to the marks to allow Swallow to enter the harbour at night during the War between the Swallows and Amazons (SA12).
Notably, the only time that Arthur Ransome directly appears as the author in the Swallows and Amazons series is when he explains the concept of leading lights:
- ...just once he [John] looked around for himself and saw the two lights one above the other like the stop called a colon, which I am going to make: there, like that. — (SA12)
And then, when we saw your lantern ... said Nancy; Lighthouse said Titty, referring to the lantern on the tree stump.
