54® Dr. Herschel’s Account of the Changes that have happened 
they should be called very small, and exzodiacal ; for, the great 
inclination of the orbit of one of them to the ecliptic, amounting 
to 35 degrees, is certainly remarkable. That of the other is also 
considerable; its latitude, the last time I saw it, being more 
than 15 degrees north. These circumstances, added to their 
smallness, show that there exists a greater variety of arrange- 
ment and size among the bodies which our sun holds in subor- 
dination, than we had formerly been acquainted with, and extend 
our knowledge of the construction of the solar, or insulated 
sidereal system. It will not be required that I should add 
any thing farther on the subject of this first article of my clas- 
sification ; I may therefore immediately go to the second, which 
treats of binary sidereal systems, or real double stars. 
We have already shewn the possibility that two stars, what- 
soever be their relative magnitudes, may revolve, either in circles 
or ellipses, round their common centre of gravity ; and that, 
among the multitude of the stars of the heavens, there should 
be many sufficiently near each other to occasion this mutual 
revolution, must also appear highly probable. But neither of 
these considerations can be admitted in proof of the actual ex- 
istence of such binary combinations. I shall therefore now 
proceed to give an account of a series of observations on double 
stars, comprehending a period of about 25 years, which, if I am 
not mistaken, will go to prove, that many of them are not 
merely double in appearance, but must be allowed to be real 
binary combinations of two stars, intimately held together by 
the bond of mutual attraction. 
It will be necessary to enter into a certain theory, by which 
these observations ought to be examined, that we may find to 
what cause we should attribute such changes in the position, or 
