I was going to adapt a standard mitten pattern, then I found out with some judicious googling that these types of mitts are called pogies and there are three patterns on Ravelry for them. I picked the pattern I liked best, but of course I am incapable of making a pattern without altering it in some way: the original pattern used a relatively thin yarn, whereas what I had to hand was thicker; I wanted to knit two-at-a-time magic loop instead of one-at-a-time on DPNs; and I wanted to do "fingertips up" rather than "cuff down" because I wasn't 100% certain I had enough yarn.
The original pattern is here (requires Ravelry login) and is copyright Fervid Designs.
I thought I'd write up my alterations to it in case anyone else ever wanted to do something similar.
Yarn
I used worsted weight yarn (the label says 4-5 sts per inch on size US 7-9 needles). The particular yarn I used was Universal Yarn Inc. Classic Worsted Tapestry, which is machine washable and 80% acrylic, 20% wool.
Needles
To match the thicker yarn I also used larger needles - US size 7 for the main body of the pogies and size 9 for the ribbing. My gauge in stockinette on the 7s was 5 sts per inch.
Pattern
Divide the yarn into two balls. Using size 7 circular needles, cast on two sets of 8 stitches, one from each ball, using the Turkish cast on or Figure 8 cast on (or your favourite sock toe cast on!). Use Magic Loop to do the following:
Round 1: knit front and back of each stitch (-> 16 st)
Round 2: knit
[Now, you have two mitten tips on your needles. When you knit a single round you are knitting the front of mitt 1, the front of mitt 2, the back of mitt 2, and finally the back of mitt 1. I find it helpful to put a marker in near the start of the first section so I know when the round starts.]
Round 3: (k1, kf&b) around (-> 24 st)
Round 4: knit
Round 5: (k2, kf&b) around (-> 32 st)
Round 6: knit
Roung 7: (k3, kf&b) around (-> 40 st)
Rounds 8,9,10,11: knit
Now you will work on the first section on your needles ONLY (the front of mitt 1. Mitt 1 is going to be the "mid pogie").
- Slip 1 purlwise, knit 19 across to end of first section.
- Turn the work, slip the first stitch purlwise and purl back 19 stitches across the same section you just knit.
Repeat these two rows, on the front of mitt 1 only, until the front of mitt 1 is 3.5" long from the point where you started this section. Finish with a knit row.
Now we will do the same with mitt 2, but mitt 2 is going to be the "end pogie" with only one cuff for the oar, so we need to do the front and back of mitt 2 together.
- Slip 1 purlwise, knit 19 to end of second section, knit 20 to end of third section
- Turn work, slip 1 purlwise, purl 19 to start of third section, purl 20 to start of second section
Repeat these two rows, on the front and back of mitt 2 only, until mitt 2 is 3.5" long from where you started this section.
Finish with a knit row.
Finally we will repeat what we did on the front of mitt 1 on the back of mitt 1, that is the fourth section on the needles.
- Slip 1 purlwise, knit 19 to end of fourth section.
- Turn the work, slip the first stitch purlwise and purl back 19 stitches across.
Repeat these two rows, on the back of mitt 1 only, until the back of mitt 1 is 3.5" long from the point where you started this section. Finish with a knit row.
Revert to working around as normal now (this means re-joining both sides of mitt 1 and the split side of mitt 2 as you go).
Knit rounds plain until you reach 3.5" from the re-joining.
Switch to size 9 needles and k2,p2 ribbing for the cuff. The cuffs need to be 2" long.
Bind off cuffs with a stretchy bind off (I like E Z sewn bind off).
Now to do the oar cuffs: one on mitt 2, and two on mitt 1. On each cuff, pick up 32 stitches evenly around the edge of the hole using the size 9 needles and do k2,p2 ribbing for 1.5". Bind off with the same bind off as the main cuff.
If you have any questions on this pattern feel free to leave a comment and I'll do my best to answer!