CHAPTER III
[Difference in Observatory and Commercial Systems]
[10.] Observatory System.
[11.] Commercial System.
[12.] Rating Card and Method of Calculating Variation
[13.] Value of the Normal Period Rate.
[14.] Definition of the Characters Used on Rate Cards
for Gain or Loss in Time.
[15.] Increasing or Decreasing the Extremes of Temperature.
CHAPTER IV