The tide recedes as I sit in the fenced garden on my roof. A jagged rock lies ready to wreck the mariner who errs. A seabird screeches somewhere to my rear. Longing, I look at the world beyond the rail. The earth is green. It is the middle of the day and I am listening to Abba. A beat of wings and the bird comes in sight - nature and I are in sync. He who renounces nature, wherever he may roam, goes nowhere.
What is my number?
Hint 1
Throw up your hands in surrender: this is one of the harder ones.