of the Georgian planet. 303 
To facilitate calculation, the observations are all given in 
mean time, and after each of them is added a theoretical ex- 
position of the place of the satellites, which I have called an 
identification, and is denoted by the sign J ; the great use of 
which will be to point out the validity of each observation, 
by comparing the observed places with the theoretical ones. 
The method of identification, which will be described hereaf- 
ter, by giving not only the angle of position at which a satellite 
ought to have been seen, but also its proportional distance in 
600 dth part of the radius of its orbit, is of great consequence 
when the orbits of the satellites are much contracted. These 
distances indeed become at last the only criterion by which 
we may know the satellites, for the angle of position, when 
the planet is near the node of the orbits, admits of so little 
change that it ceases to be a direction for identifying them. 
The same distance will also give us the total value of the 
measure of any distances taken by the micrometer, so far at 
least as to show which of them may be the most proper to 
be chosen for a more rigorous investigation. 
An identification of supposed satellites cannot be made by 
calculation ; but the observations of following and also of pre- 
ceding nights, accompanied by accurate configurations, may 
ascertain whether the object in question be of a sidereal or 
planetary nature. For if by the removal of the planet a sup- 
posed satellite be left in its former place, it is decidedly a 
star ; whereas a well ascertained absence from the observed 
place will make its planetary nature highly probable. Then 
also, if a configuration and description of every small star, 
that is situated in, and very near the path of the planet, has 
been previously made, and additional stars are afterwards 
