  The histories-based framework of Quantum Measure Theory assigns a generalized
probability or measure $\mu(E)$ to every (suitably regular) set $E$ of
histories. Even though $\mu(E)$ cannot in general be interpreted as the
expectation value of a selfadjoint operator (or POVM), we describe an
arrangement which makes it possible to determine $\mu(E)$ experimentally for
any desired $E$. Taking, for simplicity, the system in question to be a
particle passing through a series of Stern-Gerlach devices or beam-splitters,
we show how to couple a set of ancillas to it, and then to perform on them a
suitable unitary transformation followed by a final measurement, such that the
probability of a final outcome of "yes" is related to $\mu(E)$ by a known
factor of proportionality. Finally, we discuss in what sense a positive outcome
of the final measurement should count as a minimally disturbing verification
that the microscopic event $E$ actually happened.
