A steam crane on Gisborne wharf, photographed in 1889, by Daniel Manders Beere.
source: http://mp.natlib.govt.nz/detail/?id=5545&l=mi
Don’t stand under the box of rocks! (or whatever they’re using on the back end for ballast) A steam crane would be a good addition to The Port some day.
I would think that the counterweight box would slide on those rails to compensate for different sized loads being lifted.