for ascertaining the distances of clusters of stars , &c. 457 
In order to explain the construction of the table, and the use 
that is to be made of it when the situation of any one of the 
clusters delineated in figure 1 is to be examined, I shall take 
the first cluster it contains for an example. 
The first column points out the class and number, where 
the clusters taken from my catalogues are to be found, and 
only the number of those that are taken from the Connoissance 
des Temps for 1784. In the figure, the place of the cluster 
whose situation is to be examined is distinguished by the 
same mark as in the table namely VI, 7. 
The second column contains the distance of the same 
cluster from an eye placed in the centre of the globular space, 
the profundity of which is 734, as determined by the obser- 
vations that have been given. In the figure it is expressed by 
the length of the line c VI, 7 drawn from the centre of it to 
the cluster, whose length is 734, the radius of the circle 
representing the globular space being 12. 
The third column gives the angle of elevation of the 
cluster, which in the present instance is 76° 58' above the 
northern plane of the milky way. In the figure it is 
expressed by the central meeting of the lines b c and c VI, 7 : 
one of which denotes this plane, and the other the profundity 
of the cluster. 
To find the quantity of this angle, it is necessary to have 
the right ascension and polar distance of the cluster; and 
here it will be proper to notice that I have deduced these 
requisites from my own observations of the clusters, brought 
to the beginning of the year 1800. Then to find the elevation 
of the present cluster by the method which has been ex- 
plained, we have in figure 3, the side AB == 6 o ° : the side 
