  We have made a Monte Carlo simulation of the intergalactic absorption in
order to model the Lyman continuum absorption, which is required to estimate
the escape fraction of the Lyman continuum from distant galaxies. To input into
the simulation, we derive an empirical distribution function of the
intergalactic absorbers which reproduces recent observational statistics of the
Lyman $\alpha$ forest, Lyman limit systems (LLSs), and damped Lyman $\alpha$
systems (DLAs) simultaneously. In particular, we assume a common functional
form of the number evolution along the redshift for all types of absorbers. The
Lyman series transmissions in our simulation reproduce the observed redshift
evolution of the transmissions excellently, and the Lyman continuum
transmission also agrees with an observed estimation which is still quite rare
in the literature. The probability distribution of the Lyman $\alpha$ opacity
in our simulation is log-normal with a tail towards a large opacity. This tail
is produced by DLAs. The probability distribution of the Lyman continuum
opacity in our simulation also show a broad tail towards a large opacity. This
tail is produced by LLSs. Because of the rarity of LLSs, we have a chance to
have a clean line of sight in the Lyman continuum even for $z\sim4$ with a
probability of about 20%. Our simulation expects a good correlation between the
Lyman continuum opacity and the Lyman $\alpha$ opacity, which may be useful to
estimate the former from the latter for an individual line of sight.
