In order to obtain a versatile instrument for directional cosmic‐ray studies, and to investigate an indicated correlation of the soft component of cosmic radiation with the present cosmic‐ray burst studies being carried on at the University of Colorado a dual cosmic‐ray telescope was constructed. Each bank of the telescope consists of five counter trays with nine Geiger counters in each tray. The electronic circuits are connected to give three triple consecutive coincidence trains: 1, 2, and 3; 2, 3, and 4; 3, 4, and 5. By the insertion of eight centimeter‐thick lead blocks covering the sensitive area of a Geiger tray between trays 3 and 4, and 4 and 5; a separation of the components of the radiation is possible.
The telescope is adjustable in zenith in 15 degree intervals from 0 to 75 degrees from the vertical. However, in azimuth, in order to investigate asymmetry characteristics, two positions 180 degrees apart are employed. The control of the telescope is entirely automatic with the recording of data being obtained by means of periodic photographs of the indicating panel, showing the counting rate, zenith and azimuthal positions, and the time and date of the measurement. The telescope changes in zenith and in azimuth every forty minutes; the changes in zenith and azimuth being displaced twenty minutes. A cycle of operation, which consists of the step change in zenith from 0 to 75 degrees with the associated alternate azimuthal changes, requires four hours.