  We present two Rossi Xray Timing Explorer (RXTE) PCA observations of the
type~2 Seyfert galaxy NGC 4388 caught in an unusual low X-ray absorption state.
The observations were triggered by a detection in the 1.5-3 keV band of the
RXTE All-Sky Monitor. NGC 4388 was found at a somewhat high continuum level
(f(2-10 keV)=8x10(-11)erg cm(-2) s(-1)) and with a column density
(N_H~3x10(22)cm(-2)), a factor ~10 lower than normal. The second PCA
observation, four hours later, gave N_H<2x10(21)cm(-2) indicating, at the 3.1
sigma level, variability so rapid puts the absorber on a few 100 Schwartzschild
radii scale, similar to the Broad Emission Line Region, or smaller. This small
scale creates difficulties for the parsec-scale obscuring torus paradigm of
Unified Schemes for type 1 and type 2 AGNs.

Astrophysics