About the Reproducibility of the ``Melting'' and ``Freezing'' Points of Binary Eutectics

``Melting'' and ``freezing'' behaviour of Ga-In eutectic has been studied in order to find the reason for the observed irreproducibility of the ``melting'' and ``freezing'' points of binary eutectics. It is shown that reproducible results can be obtained using techniques of static adiabatic calorimetry and that dynamic methods are inappropriate if one intends to realize liquidus points of eutectics reproducibly with the accuracy necessary for high precision thermometry. The liquidus temperature of Ga-In eutectic was found to be 15.654°C. The eutectic composition is 20.5% In in Ga by weight. This value was obtained by assuming that the heat of fusion per unit mass is maximum at the eutectic composition. The value is 74 J/g.