COMMISSION 27 OF THE I.A.U.
               INFORMATION BULLETIN ON VARIABLE STARS
                            Number 1250

                                                    Konkoly Observatory
                                                    Budapest
                                                    1977 March 15


         18-CM FLUX MEASUREMENTS OF BL LACERTAE

Presented here is a small sample of 18-cm flux measurements
of BL Lacertae (VRO 42.22.01) made from October 1971 to January
1972 with the University of Illinois' 37-m (120-ft) radio telescope. 
These observations are meant to supplement data given by
Webber et al. (1976, A.J. 81, 1069). Each flux measurement represents 
the average of six scans in right ascension, six scans in
declination, and three 5 K calibrations. Two standard sources 
(observed in the same manner) were used: 3C 48 and 3C 147, with assumed 
fluxes of 15.2 and 10.5 Jy, respectively. The sensitivity of the
instrument was 5.0 Jy/K. The maximum and minimum fluxes observed
during the time span indicate a statistically significant variation, 
and the observed maximum is greater than that observed by
Webber et al. (1976), but the sample as a whole indicates that the
18-an flux of BL Lacertae was approximately constant. A small
sample of photographic photometry data over the same time span
(Deming et al. 1973, IBVS No. 821) indicates that the optical light
output was also roughly constant.

           JD      18-cm Flux (Jy) of BL Lac

       2441233.7           7.1 +-1.0
          1241.7           5.9   0.5
          1248.7           6.5   0.5
          1255.6           6.3   0.5
          1268.6           6.8   0.5
          1275.5           6.5   0.5
          1324.5           7.6   0.5

The author gratefully acknowledges the help of Dr. J. Dickel.


                                   K. KRISCIUNAS

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