The earliest account of The Upstream Worm that I have found is in the fifth edition of The Compleat Angler, published in 1676. Although the Compleat Angler is the most popular, most reprinted book in the English language (second only to the Bible), I
suspect people these days are interested in Charles Cotton's flies and fly fishing much more than in
his worm fishing. Also, his instruction on worm fishing occupies the
very last few pages of the book, and truth be told, The Compleat Angler
is a book that many people start but few finish.
Herewith, then, Charles Cotton's comments on what became known as fishing Upstream Worm.
The third way of angling by hand with a ground-bait, and by much the best of all other, is with a line full as long, or a yard and a half longer than your rod; with no more than one hair next the hook, and for two or three lengths above it; and no more than one small pellet of shot for your plumb; your hook, little; your worms, of the smaller brandlings, very well scoured; and only one upon your hook at a time, which is thus to be baited: the point of your hook is to be put in at the very tag of his tail, and run up his body quite over all the arming, and still stript on an inch at least upon the hair; the head and remaining part hanging downward. And with this line and hook, thus baited, you are evermore to angle in the streams, always in a clear, rather than in a troubled water, and always up the river, still casting out your worm before you with a light one-handed rod, like an artificial fly, where it will be taken, sometimes at the top, or within a very little of the superficies of the water, and almost always before that light plumb can sink it to the bottom; both by reason of the stream, and also that you must always keep your worm in motion by drawing still back towards you, as if you are angling with a fly. And believe me, whoever will try it, shall find this the best way of all other to angle with a worm, in a bright water especially. But then his rod must be very light and pliant, and very true and finely made, which, with a skilful hand, will do wonders, and in a clear stream is undoubtedly the best way of angling for a Trout or Grayling with a worm, by many degrees, that any man can make a choice of, and the most ease and delight to the angler. To which let me add, that if the angler be of a constitution that will suffer him to wade, and will slip into the tail of a shallow stream, to the calf of the leg or the knee, and so keep off the bank, he shall almost take what fish he pleases.
"Angling by hand" is managing the depth and drift of the bait by the way the rod is held. Besides angling by hand, the other method Cotton describes is angling with a cork or float to hold the bait off the bottom.
"Ground bait" in 1676 was a worm, grub, caddis larva, etc. as opposed to a minnow or a live mayfly.
"One hair" is a single horsehair.
"Length" is the length of a single horsehair (perhaps 24-30"), two lengths is two hairs tied end to end, and three lengths would be 6 to 8 feet.
"Plumb" is a sinker.
"Brandling" is the type of worm we call a red wiggler (scientific name eisenia fetida).
"Scoured" is kept in clean moist moss for several days. I suspect it is to empty the worm's digestive tract, but it is also said to make the worm firmer and stay on the hook better.
"The arming" where the hook is attached to the horsehair by tying silk thread around the hook and the hair (very much like laying down a layer of thread on the hook shank as the first step of tying a fly).
"Superficies" is the surface.