Temperature Too Low?

I made a batch of John Bull Traditional Ale four days ago and noticed no fermentation bubbles until 24 hours after the yeast was pitched. Bubbles came out of the trap every few seconds for about 10 hours then stopped. The OG was 1.042 and the current SG is 1.025 (both readings are corrected for temperature).

I read posts in this forum that the temperature in the primary could be as much as 10 degrees higher than ambient temperature. So, I put the fermenter in a water bath with some ice and the bath temperature was about 55 to 60 degrees F. Could this lower temperature have stalled the process? Should I be ready to pitch more yeast, and, if so, how long should I wait?

It depends on the yeast, but if your fermenting beer was at 55, yes that is a bit cool and might have stalled the fermentation. I suggest warming it back up to the preferred range of the yeast, perhaps a bit on the high side (e.g., 65 - 68 would be a typical range for many yeasts). Once it was warmed, gently swirl/agitate the fermenter to get the yeast back in suspension. Fermentation will probably pick up again. If not, then pitch some new (rehydrated!) dry yeast.

Hope it all works out!

agree with above advice 100%

beer is not done fermenting...let her warm back up and give it a gentle rock. I'd expect a final gravity more like 1.010

The instructions recommend FG of 1006 (998 for diabetic beer).