...Fels Naptha! (Okay, you probably could have figured this out from the photo). This is a lye-based laundry soap bar that is used to remove stains. Unfortunately, the grocery stores in the area haven't seemed to have figured this out, and stock it with the regular soap. So I had to go online to find a photo to hone my pattern recognition skillz, and still wander the aisles before finding it.
Method: fill up half of double-sided sink with hot water, dunk kitty pi in for a few minutes, and transfer to other side of sink. Soap up both sides of the parts that I wanted especially to refelt. Put in pillowcase, set washer for eight minutes, go away since I'm sick of trying to figure out how the washer works (and figure it is better left alone anyway). Come back and take out near beginning of spin cycle.
Take bed out of pillowcase; aaaahhhh!!!! moment, it is as small as a hat! (Okay, a hat for a giant). Take upstairs to the implements that I used to mold it before, a 12" Calphalon pot with a bath towel wrapped around it. Get it over the pot, and frantically try to stuff towel around sides. Cat looks on with interest at insane human. Does she know that she gets the bed if I overfelted it? Did she use her super mind powers on me? Hmmm. You be the judge:
Fit towel around pot, stuff matching hand towel in for good measure. Hmmm, it is already pretty dry from starting the spin cycle. Take to kitchen sink and pour hot water over it from a glass to get it wet again. Leave it to dry overnight. I think it lost about two inches diameter in all, from about 17.5" to 15.5". It was really a stretch to begin with, and fits Savannah much better. So I suppose this is the trial run, and I will knit another bed for Cobie. I was a little dubious about the instructions to just keep knitting more rounds for a larger diameter bed, with no increases. The bottom of the bed is essentially the first 24-26 of the 30 rounds knitted straight, with the extra rounds that I did essentially serving to make the sides higher (which I don't want). So next time, I'm going to do another set of increases after row 24, and knit at least 6 and possibly 12 rounds after. There were about 40-42 rows, which felted to a radius of about 7 3/4". So 6 to 12 rounds should give me about 2-4 extra inches in diameter, for 17-19". Also, I think I will play around with the needle size, and maybe go up to a 13 for the circulars (and try the different needle tip idea I had).