320 PROCEEDINGS OP THE AMERICAN ACADEMY 



Photometric observations of all the stars with which variables are 

 known to have been compared have been undertaken at the Observa- 

 tory of Harvard College, to which all observers are requested to send 

 lists of the comparison stars employed by them, or references to the 

 published places of such stars. The lists of Argelander, Schonfeld, 

 and Oudemans form the foundation of the work, but information of 

 many comparison stars not included in those lists has been received, 

 and these stars are also to be observed. 



It is hoped that it will ultimately be practicable to give the number 

 of observations of each variable star which have been made each year 

 since its discovery. Any information of this kind, hitherto unpub- 

 lished, will therefore be gratefully received. 



It is much to be desired that observers stationed in the southern 

 hemisphere should pay some attention to the variable stars which their 

 situation gives them special facilities for observing, and should send 

 some notice of their work for appearance in this series of publications. 

 It will be seen on examination that no variables in large southern 

 declinations are known to have been recently observed. 



The present report relates principally to observations made during 

 1885; but earlier observations, notice of which has been received since 

 the last report was published, are also mentioned in it. The observers 

 whose work is here stated are named below in alphabetical order, with 

 the abbreviations employed to designate them in the subsequent tabu- 

 lar statements. 



B. These observations were made by Mr. T. W. Backhouse, of 

 Sunderland, England, where most of the comparisons were made. A 

 refracting telescope by Cooke, aperture 4^ inches, magnifying powers 

 38 and 75, was often used ; other observations were made with the 

 finder, power 9, and the rest with a field-glass and similar instruments 

 of low power, or with the naked eye. The methods of comparison 

 were chiefly three : that of Argelander, that in which the relative 

 brightness of the star observed is indicated by a fraction of the appar- 

 ent difference between two comparison stars, and that of verbal de- 

 scription, in which, however, the words employed are regarded as 

 having numerical values. A copy of the observations has been sent 

 to the Observatory of Harvard College. 



D. These observations were made by Dr. N. C. Duner, at the Ob- 

 servatory of Lund, Sweden, according to the method of Argelander. 



Ee. These observations were made by Mr. John H. Eadie, at 

 Bayonne, New Jersey. The telescope employed was made by John 

 Byrne ; its aperture is 3^ inches, and the lowest magnifying power 



