CATALOGUE OF THE MAGNITUDES OF SOUTHERN STAES. 3 
Method of Reduction, 
The reduction of the sequences was j^erformed graphically by plotting each 
sequence on squared paper, the U, A. magnitudes helncr used as ordinates. and 
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the observed differences of brightness, expressed in. steps, as abscissas. Thus, 
in the sequence a2b3cld2eS/, the several stars would be indicated in the 
plotting by dots with the abscissas a = 0, h = 2, c= 5, d = ^, e = 8, and /= 11, 
and ordinates corresponding to the U. A. magnitudes for the several stars. The 
middle points between these dots, taken two and two, were then carefully in- 
serted by measurement, and a straight line drawn so as to represent as well 
as possible all these points of bisection. The value of tlie ordinate, to the 
nearest half-tenth, was then read off, corresponding to the abscissa for each 
star. The magnitudes so deduced were then entered against the several stars 
in the record-book, and are the same as appear in the present Catalogue. The 
process thus described was uniformly pursued in the reduction of the sequences. 
There were, however, many observations made not in the form of regular 
sequences, consisting of comparisons of particular stars with several neighbors. 
Most of these observations were made in the final revision, in the case of in- 
sufficiently observed stars, or where large discordances gave rise to suspicion of 
variability. The magnitudes deduced in such cases were found simply by taking 
the means of the results of the separate comparisons. 
Formation of the Catalogue* 
The results of the observations were now collected to form the Catalogue. 
The stars w^ere copied from the record-book upon cards. Each card contained 
the U. A. number of the star, its position and magnitude, and my separate 
observations. It w^as during this process that the stars which had been insuffi- 
ciently observed were detected. 
The cards were then arranged according to right ascension, and the results 
copied in the Catalogue. Those stars not contained in the U. A. Catalogue, al-- 
though as bright as T\ were inserted in their proper places. 
In the first column of the Catalogue is the current number of the star. 
The second contains the U. A. Catalogue number. 
The third contains the constellation. 
In the fourth and fifth columns are the rig-ht ascensions and declinations for 
