HST STIS observations of four QSO pairs

We present HST STIS observations of four quasar pairs with redshifts 0:84 200 km s 1 . This probably reflects the fact that the scale probed by our observations is not related to the real size of individual absorbers but rather to large scale correlation. Statistics are too small to conclude about any dierence between pairs separated by either 2 or 3 arcmin. A damped Lyman- system is detected at zabs= 1:2412 toward LBQS 0019 0145A with log N(Hi) 20:5. From the absence of Znii absorption, we derive a metallicity relative to solar (Zn=H)< 1:75.