I quite postitive i saw it somewhere before, maybe for a magic trick…
http://people.ex.ac.uk/rbd201/riddle9/whynot.htm
What’s the knot at the bottom of the page?
if my knot book wasnt boxed up in the storage unit right now I’d bee all over that, all I can say is it looks really familiar
I believe it’s known as a true lover’s knot (sometimes called a fisherman’s knot).
It’s a tangle, and I’d call it
(IUI)(X[sup]-[/sup]X[sup]+[/sup])(X[sup]-[/sup]II)(X[sup]-[/sup]X[sup]+[/sup])(I^I)(IUI)(X[sup]-[/sup]X[sup]+[/sup])(IIX[sup]+[/sup])(X[sup]-[/sup]X[sup]+[/sup])(I^I)
Then again, maybe I’m being too technical.
Fisherman’s knot. (I’ve never heard it called a “true love’s” knot, but I may just move in the wrong circles.)
This site calls it by both names, but in other searches I turned up at least four separate different knots call “true love®’s knot.”
My googling agrees - this name seems to be rather freely used. I need to dig out my Ashley Bok of Knots for the definitive answer (if there is one).
Bok = Book
Hubby just finished his high angle rescue instructor’s course. He agrees with fisherman’s knot. He has never heard of the true love’s knot.
That knot is listed in Ashley’s about a dozen times, and it goes by quite a few different names depending on who you ask. The visual entry that matches the OP’s illustration exactly has the following entry:
The names of knots also depend on the size of the material being used, use fishing line it’s one name, use rope and it gets another !
A sheep shank- used to shorten a rope, right? Also known, as you’ve said, Fisherman’s knot, b/c it’s used to shorten ropes used to anchor a boat to the dock?
I’m an eagle scout.
One glance at that tells me it is a Sheepshank.
I was hoping to say “I knows knot”
It’s not a sheepshank. A sheepshank is knotted in a single rope, and the knot shown in the OP is composed of two ropes. Wiki has the OP’s knot listed as “Canonical Name: Fisherman’s knot Variant Name(s): Waterman’s knot, angler’s knot, englishman’s knot.”
My father’s father was a commercial fisherman, and my father taught his kids some useful knots. He was most insistent that we learn the bowline knot, for instance, claiming that it was an excellent loop to throw to someone in the water.
I hate to disagree with Ashley but I don’t think it is a particularly good know. Two overhand knots are twice as hard to untie as one after the knot has been strained.
If you want to tie two ropes, lines or what-have-you together use either asheet bend, or if you really want to be secure acarrick bend.
This would indeed be a poor choice if the knot must be untied after taking a strain. But tied in a fishing line (as Ashley suggests), you almost never plan to untie it - you simply cut it out.
A carrick bend is indeed a useful knot and it should be better known. But it is way too bulky (and probably too slow to tie) for use by an angler.
But it’s also called a lovers’ knot and everyone knows that lovers frequentyl want to be untied. 
The double fisherman’s knot (with a double overhand in each rope) is also called the “grapevine knot”, and is familiar to climbers. Yes, it is very difficult to untie after the rope has taken a load. Usually, it is used to tie short pieces of cord into loops, and you don’t intend to ever untie them.
Oh, and what I learned as a “water knot” is something else - it’s used to tie webbing or straps together, and is formed by following an overhand bend in one webbing end by the other laid flat on top of it. Here:
http://www.ruckus.org/article.php?id=115&printsafe=1
Some references seem to suggest that this is also called a “tape knot” or a “ring bend”, but I learned it as a “water knot”. Again, once the webbing has taken a load, you’ll have a hell of a time untieing it. You can do this with ropes, too, but it’s most convenient for flat webbing.
I’ve always known it as a sheepshank also. It’s a fun knot to tie when you’re bored of whittling!