168 Dr. Herschel's Method of observing the 
of an equality and an equal distribution of stars to which we 
have referred, is too far from being strictly true to be laid 
down as an unerring guide in this research. The stars of the 
first and second class, when scrupulously examined, evidently 
prove that if we would be accurate, we must admit them, in 
some degree at least, to be either of different sizes, or placed 
at different distances. Both varieties undoubtedly take place. 
This consideration alone is fully sufficient to shew, that how 
much truth soever there may be in the hypothesis of an equal 
distribution and equality of stars, when considered in a gene- 
ral view, it can be of no service in a case where great accu- 
racy is required. 
Since therefore it appears that in the classification of stars 
into magnitudes, there either is no natural standard at all, 
or at least none that can be satisfactory ; it. follows, that astro- 
nomers who have classed them thus, have referred their size 
or lustre to some imaginary idea of brightness. The great 
number of stars, indeed, which have been placed into every 
particular class, may assist us to form a kind of confused type 
in our minds, by which we may be enabled to arrange others ; 
but how doubtful this must ever remain, we may see from the 
circumstance of the intermediate expressions that have been 
introduced. 
1.2 m* for instance, denotes that a star so marked is 
f between the first and second magnitude. 2.1 m signifies 
the same thing, with an intimation that the star so distin- 
guished is nearly of the second magnitude, but partakes still 
something of the lustre of a star of the first order. With 
stars of- the first, second, and third classes there may be some 
* I use the letter m in a short way to express the magnitude of the stars. 
