Parallel proton temperatures between 20 and 160 solar radii, measured for two averaging times. The red curve of (n/B)² is proportional to the parallel temperature expected in the absence of heating or cooling. It extends to only about 70 solar radii because there were no sufficiently reliable plasma density measurements beyond that point. The agreement between the three curves shows that there was neither heating nor cooling of the parallel electrons below 70 solar radii.