V728 Herculis - an active W Ursae Majoris system of F spectral type Observations made of the short-period eclipsing binary system V728 Herusing a photoelectric telescope on four nights in June 1988 at LowellObservatory are presented. Three times of minimum light were revealed byobservations covering the eclipse portions of the light curves. A periodstudy covering 80 years of observations indicates that a drastic periodincrease may have recently occurred, while indications such as apossible reversal of eclipse depths may suggest that V728 Her ismagnetically active. Standard magnitudes derived for V728 Her and forcomparison and check stars indicate that V728 Her is approximately ofspectral type F3 while the comparison and check stars are K type. Apreliminary light-curve solution indicates that the system consists oftwo nearly equal temperature components in the spectral class F3 to F4in contact with a substantial fillout of near 20 percent and a massratio of about 0.4. This degree of contact is supported by the positionof V728 Her on the period, color plane of Eggen. The period increase mayindicate a mass exchange from the secondary to the primary component ora catastrophic angular-momentum loss due to an episode of massivestellar wind expulsion along lines of a corotating magnetic field.
B and V light curves of TY Bootis The short-period eclipsing binary system TY Boo was observed on fiveconsecutive nights with facilities at Lowell Observatory. Theobservations covering the eclipse portions of the light curves yieldedfive epochs of minimum light. The light curves, defined by 348observations with the B filter and 353 with the V filter, are of the WUrsae Majoris type and are symmetric. The system becomes redder duringeach eclipse with a momentary dereddening at phase 0.0.