.... coz I was restless and couldn't sleep, about how items get the most unusual and misleading names.
Building overhead lines, one uses a square curved washer where bolts go through the pole before applying the nut. Nowadays they're just a stamped and shaped item about 2" square.
Back in the 1930s one of the private companies, Edmondsons, used a cast washer, much heavier and altogether more aesthetically pleasing. The drawing number for this item - everything had a drawing - was E22.
It turns out that E22 was also the item in the rule book for the GWR governing working on wet days. I guess someone who had worked for both GWR and Edmondsons had christened them thus.