It is generally known that intensity of the 530.3 nm coronal line depends on tho solar aetivity. The proposed coronal index /Cl/ represents the|530-g nm line irradiance from the whole corona as it seen from the Earth in W8r“^xl0^ . The Cl is derived from daily measured intensities around the disn of the Sun. Maximum
values of the Cl were observed in the second half of the year 1981, just before a deep decrease in the Wolf´s number. Monthly average values of the Cl in the cycle 21 vary from 1,64 to 18,93. The rough comparison of the Cl with similar indices of the UV emissions shows a relative good agreement.
We present the preliminary results of a study of the solar prominences observed at Lomnický Štít coronal station with the 20 cm coronagraph during the ascending phase of cycle 22. The observational material was processed and a catalogue of prominences was prepared. On the basis of this catalogue some statistical results were obtained. They concern mainly the latitudinal, longitudinal and time distributions of the prominences and their basic morphological characteristics.