Yesterday, after untangling massive snarls from one of the anchor rodes, I was inspired to get cracking on my cockpit mat so I can rid the storage areas of another 100' or so of 3/4" manila line.
Again using Hervey Garrett Smith's "The Art Of The Sailor", I opted to tie an Ocean PLat Knot. This is very similar to the Turk's Head knot except that it's oblong instead of round.
I laid the line out on the dock and started laying out the knot:
Sharp-eyed readers might notice that this mat isn't strictly correct. Some of the runs are 5 strands wide and others are only 4. I should have stopped at 4 but I thought that maybe I'd have enough to make one more complete round. I didn't. But I liked how it looked so I decided to not remove the offending run.