The jetty

Used to take away blue elvan from Penlee Quarry perhaps?

Refueling jetty for the old seaplane base?

One of my smaller projects, I will look out my OS map and notes. WWI base. The area behind the South Pier was that base.
All quarry stone was transported, by the most westerly railway, to South Pier, I have some notes on that on the page on SS WOODTOWN on Hearts of Oak.