A method of measuring a volume of a storage container using a plurality of acoustic devices (120A-120C, 130A-130B), the plurality of acoustic devices including a transducer and one or more sensors (120A-120C), the method comprising: deploying the plurality of acoustic devices into respective positions on an exterior surface of a circumferential wall of the container, wherein the one or more sensors are acoustically coupled to the surface and configured to detect pulses propagating along the surface, and wherein the transducer is acoustically coupled to the surface and is configured to generate one or more pulses that radiate along the surface away from the transducer and toward the one or more sensors in at least a first circumferential path and a second circumferential path; generating one or more pulses using the transducer, wherein each pulse is generated at an impulse time; detecting, using the one or more sensors, the one or more pulses radiating along the first circumferential path and the second circumferential path and recording a respective time that the one or more pulses radiating along a respective circumferential path are detected; calculating, by a computing device in electronic communication with the one or more sensors based on the impulse time and respective detection times, respective times of flight -TOFs- for the one or more pulses, wherein each respective TOF is an elapsed time for the pulse to travel between two of the acoustic devices along a particular circumferential path the method being characterized by : calculating, with the computing device, respective distances between the acoustic devices in each of the first and second circumferential paths based on the respective TOFs and a speed of sound through the wall; and determining, with the computing device, the volume of the storage container based on the calculated respective distances. deploying the plurality of acoustic devices into respective positions on an exterior surface of a circumferential wall of the container, wherein the one or more sensors are acoustically coupled to the surface and configured to detect pulses propagating along the surface, and wherein the transducer is acoustically coupled to the surface and is configured to generate one or more pulses that radiate along the surface away from the transducer and toward the one or more sensors in at least a first circumferential path and a second circumferential path; generating one or more pulses using the transducer, wherein each pulse is generated at an impulse time; detecting, using the one or more sensors, the one or more pulses radiating along the first circumferential path and the second circumferential path and recording a respective time that the one or more pulses radiating along a respective circumferential path are detected; calculating, by a computing device in electronic communication with the one or more sensors based on the impulse time and respective detection times, respective times of flight -TOFs- for the one or more pulses, wherein each respective TOF is an elapsed time for the pulse to travel between two of the acoustic devices along a particular circumferential path the method being characterized by : calculating, with the computing device, respective distances between the acoustic devices in each of the first and second circumferential paths based on the respective TOFs and a speed of sound through the wall; and determining, with the computing device, the volume of the storage container based on the calculated respective distances. calculating, with the computing device, respective distances between the acoustic devices in each of the first and second circumferential paths based on the respective TOFs and a speed of sound through the wall; and determining, with the computing device, the volume of the storage container based on the calculated respective distances. <EOS>