Irish Moss Stitch

Irish Moss Stitch as instructed in Knit Stitch Guide by Rita Weiss

It took one frog and restart to understand this stitch, but it is fairly simple. The instructions are interesting in that they start with one row of K1P1, then the main pattern of 2 x P1K1 and 2 x K1P1, and ending with another single row of K1P1. Obviously, when the pattern is repeated the last and first rows combine to make a block of the same pattern. 

So far, it feels as if all these patterns are actually one slice of a larger pattern — although i guess that's the point, you can repeat to your heart's content for any type of garment.