Oh! The pain!
The yeast I pitched in my last recipe, a knock-off from the Old British Beers book, appears to have failed. It was a Wyeast "smack pack" liquid culture. I got on the company website and it stated that a culture could take up to 36 hours to get going. After about 40 nothing was happening, so I pitched a Nottingham dry yeast. Hopefully this will save things.
Looking back over my brewing notes, I see that of the last four times I have used Wyeast cultures: Two have failed, one underperformed, and one (Scotch Ale) worked excellently. I am not sure what the problem could be. I had made a note that only the Scotch Ale pouch had inflated prior to pitching and that was the only one that I smacked the night before brewing. The others were all smacked the day of brewing but still had 6-8 hours before pitching. Maybe that is the key. However, the Wyeast website does say that the pouch need not be inflated prior to pitching.
I know many people swear by Wyeast products, so if anyone has an idea what went wrong, please pass it on.
Thanks and Cheers!