  We present collider tests of the recent proposal for weak-scale quantum
gravity due to new large compact space dimensions in which only the graviton
($\G$) propagates. We show that the existing high precision LEP-I $Z$-pole data
can impose non-trivial constraints on the scale of the new dimensions, via the
decay mode $Z\to f\bar{f}+\G$ ($f=q,\ell$). These bounds are comparable to
those obtained at high energy colliders and provide the first sensitive probe
of the scalar graviton. We also study $W(Z)+\G$ production and the anomalous
$WW(ZZ)$ signal from virtual $\G$-states at the Fermilab Tevatron, and compare
them with the LEP-I bound and those from LEP-II and future linear colliders.
