  We have tested a prototype time-of-flight system based on bulk scintillator
block of dimensions $2.5 \times 2.5 \times 200$ cm. Using a calibration scheme
similar to the one used in actual collider experiments, we have achieved a
resolution of 71 ps using Amperex XP2020/UR photomultipliers and 81 ps using
proximity-focusing fine-mesh photomultipliers (Hamamatsu R2021). Results are
also obtained for scintillating fiber blocks of the same dimensions. Good
internal reflectivity of the bulk scintillator block resulted in resolutions
superior to the fibre blocks. A single-photon pulsed laser system was used to
study photomultipliers and the results were used in a Monte Carlo simulation of
the system to study the critical elements that determine the resolution.
