Now consider the case where <math>T_1</math> is a fixed reference temperature: the temperature of the triple point of water. Then for any T<sub>2</sub> and T<sub>3</sub>, | Now consider the case where <math>T_1</math> is a fixed reference temperature: the temperature of the triple point of water. Then for any T<sub>2</sub> and T<sub>3</sub>, |