The derrick is another lifting device used on stations that do not have a rock in the sea for a highline and where seas were also relatively calm. It was used like the highline to lift and lower items to and from the work boats or lower the keeper’s boat or station boat in and out of the water.
Definition – “a derrick is a lifting device composed of one mast or pole which is hinged freely at the bottom. It is controlled by (usually 4) lines powered by some such means as man-hauling or motors, so that the pole can move in all 4 directions. a line runs up it and over its top with a hook on the end, like with a crane. It was commonly used in docks.”Derrick (Lifting Device), 28 april 2006 12:06 UTC, Wikipedia, The Free Encyclopedia
By the way, to add to your list of unnecessary information, “the device was named after Thomas Derrick, an English executioner from the Elizabethan era because of its resemblance of the frame from which a hangman’s noose hangs.” (citation as above)
Thanks to Mike Higgins, Principal keeper at Boat Bluff, I have some good photos to show you about the equipment and it’s operation. I’ve explained where I can but I never ran a derrick in my life – 29 years on highlines! I’m hoping that Mike will fill in the blanks in the future when he has time. For now all I can tell you is that it runs with cables and hydraulics whereas the highline only used cables.
Another very useful piece of equipment!
A gallery of photos showing the derrick at Boat Bluff, with thanks to Mike Higgins.