How to measure emf of a thermocouple using potentiometer?

Constant resistance potentiometerThe constant resistance potentiometer is a variation of the basic idea in which a variable current is fed through a fixed resistor. These are used primarily for measurements in the millivolt and microvolt range. Microvolt potentiometerThis is a form of the constant resistance potentiometer described above but designed to minimize the effects of contact resistance and thermal emf. This equipment is satisfactorily used down to readings of 1000 nV or so. Thermocouple potentiometerAnother development of the standard types was the 'thermocouple potentiometer' especially adapted for temperature measurement with thermocouples. [4] Potentiometers for use with thermocouples also measure the temperature at which the thermocouple wires are connected, so that cold-junction compensation may be applied to correct the apparent measured EMF to the standard cold-junction temperature of 0 degrees C. Analytical chemistryTo make a potentiometric determination of an analyte in a solution, the potential of the cell is measured. This measurement must be corrected for the reference and junction potentials. The concentration of the analyte can then be calculated from the Nernst Equation. Many varieties of this basic principle exist for quantitative measurements.