Further on the Aran wool. The original wool used in the Aran Islands was also called baineen. It was homespun wool, spun in the greese. That is, unwashed, and with the lanolin from the sheep still in the wool, making it semi waterproof. The thickness, as homespun, was pretty much variable ranging from fingering weight thru light sport, and even up to full worsted weight or bulky. There was no specific size, and the sweaters originall made for the fishermen were much more simple in design. The beautiful stitches we see on sweaters called Aran sweaters now days actually did not surface intil the late 30's or early 40's, and were mainly a creation of the Patton Yarn company, for the women of the islands to use in a cottage industry to help earn an income for their families. There is now circulating a story that the patterns were specific to families, and that a drowned fisherman could be identified by his sweater patterns. This is a nice tale, but essentially not true. The patterns represented such things as the rock walls around family farms, diamonds for a hope for wealth and good luck, wheat sheaves, cables representing fisherman's ropes, etc., put together in myriad fashion according to the skill or creativity of the individual knitters. There was not originally any clan or family association. That came along later as a sort of folk lore to make the knitting more popular with non-island consumers. Patterns were mainly memorized, and passed from knitter to knitter just as patterns sometimes are today. Some knitters may have made many sweaters in the same design, but that was mainly because once a knitter learned how the stitches were done for a particular combination of patterns, it was easier to use one sweater as a guide to making others than it was to create a completely new design and go to the trouble of getting the stitch count right, and learning the ins and outs of a different combination of stitches. Most of the traditional Aran knitters used the same stitches over and over because they liked them, not because of any family or clan association. Any knitter on the islands (there are 3 islands in the Aran group, though only the largest is well populated) was free to use whatever stitches they wanted.
The sweaters sold by the islanders in their Aran Sweater Store on the south island now days are made from commercially milled yarn very much like the Patton and Lion Brand yarns which are availble in craft stores most everywhere. What is usually referred to as "Aran" wool is now approximately DK or light worsted weight, generally knit with either a number 7 or 8 American size needle. There are several books and individual patterns available on the market, and some free ones and paid ones can be downloaded from lionbrand.com and pattonsyarn.com
The beautifully patterned sweaters they are offering are several generations removed from the simple stockinette or ribbed "ganseys" or fishermen's sweaters that originated in the Aran Isles. Those were made in homespun yarn which was generally worked as "singles" or single-plied yarn, and was worked on needles small enough to make the knitting dense, and almost waterproof, though the sweaters, oddly, seem to give off a bit of heat when they are wet, and the fishermen could be seen to be a bit steamy when they came in from a rainy or foggy trip in their open boats. This insulative property made the sweaters good protection from the elements, as they feel warm even when wet, as long as the wind chill isn't too bad. The teddy bear in my Avitar picture is wearing an Aran sweater made specifically for him about three weeks ago from a free pattern from aranknits.com (Grandma on the Mountain).