COMMISSION 27 OF THE I. A. U.
          INFORMATION BULLETIN ON VARIABLE STARS
                       NUMBER 870

                                 Konkoly Observatory
                                 Budapest
                                 1974 February 16


           1973 PHOTOMETRY OF V725 Sgr



    The unique variable V725 Sgr was discovered by Swope (HA
105, 499, 1936) and re-observed in 1968 and 1969 by Demers (RASC
Journ. 67, 19, 1973). In 1926 the variable exhibited a 12-day 
periodicity which increased by approximately one day per year,
reaching a maximum period of 21 days in 1935. Since 1935, 
however, V725 Sgr has only shown non-periodic variations of low
amplitude.
    V725 Sgr was observed during 1973 to determine whether
the star is slowly becoming systematically brighter, as suggested 
by the 1968 and 1969 observations. The variable was observed
seven times by visiting and resident astronomers using the 24"
(60 cm) reflector of the University of Toronto at the Las Campanas 
Observatory of the Carnegie Institute of Washington. The
observations are given in Table I, where Delta V=V(725)-V (1). Photoelectric 
measures were made during regular observing sessions.
Photographic plates (103a-D+RG495 and 103a-O+GG385) were calibrated 
by the sequence of Demers.

       Table I. 1973 Observations of V725 Sgr.

J.D.       V     Delta V B-V
2441000+
771.89   12.28   0.03   1.25   p.e.
791.78   12.45   0.22   1.32   p.g.
800.820  12.55   0.32   1.45   p.e.
842.85   12.58   0.35   1.49   p.g.
852.557  12.52   0.29   1.33   p.g.
927.589  12.31   0.06   1.34   p.e.
954.508  12.48   0.25   1.34   p.g.

    In 1973, V725 Sgr achieved new maxima relative to recent
years. Although only seven observations are available, the data
are not inconsistent with a period of 50 days and an amplitude
of 0.40 magnitudes (see Figure 1). The mean brightness may also
be increasing as indicated by the averages for the last three
observing sessions, but the data are few and the secular increase
is small with respect to the short-term amplitude. However, if the
present behaviour is similar to variations at the end of the 19th
century, the variable should continue to increase its brightness
in the coming decades.

       Averages

              V     B-V    n
1968        12.59   1.36   19
1969        12.52   1.32   19
1973        12.45   1.36   7


                       [FIGURE 1]


   We wish to thank Derrick Salmon and Chris Smith, resident
astronomers at Las Campanas, for making some of the observations
reported here.







SERGE DEMERS                BARRY F. MADORE
Laurentian University       David Dunlap Observatory
Sudbury, Ontario, Canada.   University of Toronto
                            Toronto, Ontario, Canada.