1 Introduction

In 1982 we initiated a systematic program of astrometric observations of natural satellites of the Jovian planets. The results of our Uranian observations, which correspond to 701 images of the system, were presented in three previous papers (Veiga et al. 1987; Veiga & Vieira Martins 1994, 1995). These sets of positions are some of the largest and most accurate in the catalogue of all available published and unpublished Earth-based observations of the satellites of Uranus compiled by Taylor (1998).

In this paper the observations of 750 frames carried out during 35 nights distributed in 12 missions in the 1995-1998 period are presented. Almost all observations were taken near the zenith since the latitude of our telescope ($-23^\circ$) is close to the declination of the planet in this period.

The paper is organized as follows: in Sect. 2 the observations and reduction procedures are presented; in Sect. 3 the observed and calculated positions are compared. The conclusion is presented in Sect. 4.