Refractive indices n of coexisting phases and turbidity tau of an homogeneous sample of the ternary system water+3-methyl pyridine +sodium bromide were measured near its lower consolute point. In both cases, the global composition of the samples was fixed (0.170 mass fraction of sodium bromide, 0.599 mass fraction of water). The system was previously reported to exhibit a tremendous change in the critical exponent gamma as the salt concentration increased from 0.08 to 0.17 mass fraction. Data also recorded a marked increase in the background turbidity, and the system was therefore suspected of displaying multicritical behavior. Refractive index measurements were carried out in the reduced temperature range 1x10(-4)less than or equal tot=(T-T-c)/T(c)less than or equal to0.02. Turbidity data were obtained for 6x10(-4)less than or equal totless than or equal to0.032. In addition, electrical conductivities of the solution were measured as a function of the concentration of salt, in the homogeneous region along an isothermal (298.12 K) path of fixed 3-methyl pyridine/water ratio. Although critical coordinates of our sample agree with those previously reported, we were unable to see any trace of multicritical behavior. (C) 2003 American Institute of Physics.