Abstract: The invention relates to apparatus for measuring storage parameters such as level and temperature relating to immiscible liquids or fluids in a tank. The apparatus comprises a pulse generator (1) for generating pulses which are applied to a delay line (3) with reflected pulses being representative of the depths of the various liquids constituting propagation transitions through different media (I, II, III, IV, etc.). Logic means (Li) are switched on by a measurement pulse (Im) and they are switched off by corresponding reflected pulses (Ii) generated by transitions of order i. Integrator means (Ji) for integrating the signals delivered by the logic means (Li) serve to generate respective voltages proportional to the time lapse between the measurement pulse (Im) and each of the reflected pulses (Ii) under consideration. Multiplexer means serve to sequentially deliver the measured values corresponding to the different liquids of order i in the tank.