This knot is mentioned in Ashley Book of Knots #1763. However it does not have a name and also I think the Prusik’s knot true potential was knot known then. The Prusik knot has become very popular as good knot that does not slip when under load.
? Fisherman’s Knot: https://youtu.be/tBwhgDPKxh0
? Adjustable Jug Sling: https://youtu.be/BhVBHoB910A