Techniques and apparatus for the accurate and fast measurement of temperature and speed at many ``points'' within a fluid are described. Using bead thermistors in liquids and a digital data acquisition system, up to 150 measurements/sec can be made for (1) temperatures within and beyond the range from 10 to 40°C to an accuracy of ±0.01°C and (2) speeds in the range from 0 to 5 cm/sec to an accuracy of ±0.1 cm/sec. The very small size of bead thermistors now available with bead diameters less than 0.25 mm and with lead diameters less than 0.025 mm, means that many of these transducers may be mounted with small or negligible disturbance to the flow. A mounting configuration where the beads are supported only by their leads is described.