This is part of the "traditional." Open fermentation. In this
low-ceilinged fermentation room there were at least four different shapes
of fermenters, clearly varying in age significantly. The brewery also has
a cooperage which makes and repairs their wooden barrels (not all their
beer is served "From the Wood," but quite a bit of it is)
and two working 19th-century steam engines.
Here's more of the "traditional." When the yeast ferment the
sugars, they give off heat (that's called an exothermic reaction). Rather
than use jacketed stainless steel cylindroconical fermenters, Young's still
uses these open fermenters with attemperators to keep the temperature of
the fermenting beer from getting too hot. Most modern breweries use tanks
that are cylindrical at the top and conical at the bottom (so the yeast
collects and can be drawn off neatly at the bottom of the cone) and have
tubes or plates that form a jacket around the outside of the fermenter.
In these traditional fermenters, the copper pipes are mounted inside
the fermenter. Cold water is run through the pipes to cool the fermenting
beer. In modern fermenters, water or glycol (antifreeze) is circulated
through the jacket by a refrigeration unit.