392 



PEOCEEDINGS OF THE AMERICAN ACADEMY 



placed before 81°30. The other residuals show a good agreement 

 between the estimates and measures. The Durchmusterung magni- 

 tudes also agree well, if we correct for the difference of scale, which 

 makes the residuals for faint stars negative and for bright stars 

 positive. 



The individual comparisons by M. Glasenapp are detailed in Table 

 XIII., which gives a current number, the Moscow mean time, and the 

 corresponding light in grades. By the formula 1.00 -|- 0.07 g these 

 are reduced to the same scale of magnitudes as that used in meas- 

 uring the light in Table XI. The results are given in the fourth col- 

 umn. The next column gives the time of minimum derived from each 

 of these observations by means of the light-curve adopted in Table XI. 

 The last column gives the error in the oljservation of M. Glasenapp, if 

 we assume the minimum to have occurred at 9"^ 47™ Moscow mean 

 time. 



TABLE XIII. — M. Glasexapp's Compaeisoxs of DM. 81°25 on July 3 



The error in the estimated light of DM. 8l°18 seems to have af- 

 fected the last measures of the variable. It would appear that after 

 increasing for over two hours (or three hours after the minimum), the 

 variable had not attained the brightness of DM. 8l°30, or 18.3 grades ! 

 The last five observations have accordingly been bracketed. The 



