Tom, Danny and I ran around the college loop. Cool conditions. I tried to stick to running the flats and downhill and walked the ups. Finally at around 45 minutes my left calf cramped and I walked. After about 50 meters it relaxed and I dropped into a 200-300 meter run, 100 meter walk pattern on the track (F L A T) until I had completed an hour. No more problems.
Later on I walked thirty minutes with Lucy.
The calf is still not right. It could be I overdid it with the tennis ball routine. I'm going to stick to the flats for the time being and see if I can run through it.