45$ Sir W. Herschel’s astronomical observations 
AC = 71 0 17', being the polar distance of the cluster; and 
the angle A = 6° 56' 45'', being the right ascension of the 
cluster 196° 56' 45" minus 190°. By these quantities we find 
BC == 13° 2' 28", and its complement 76° 57' 32", which is 
the required elevation of the cluster VI, 7. 
The fourth column assigns the azimuth of the cluster; and 
as the degrees of the quadrants of the azimuth circle in figure 
2, are numbered one from the south the other from the north, 
the letter S is prefixed to E, to show that the degrees of it 
are to be looked for in the south-east quadrant ; the quantity 
of the angle, in consequence of the foregoing calculation, is 
easily obtained ; for as we now already have the side BC, the 
opposite angle A, and the side AC, we find the supplemental 
angle CBD, which gives the azimuth 31 0 43' 9". By this 
result the situation of the direction, in which an observer in 
the centre of the globular space must look to see the cluster, 
is determined. 
The fifth column contains the point of sight, or situation 
in which the eye of an observer should be placed, when, by 
the assistance of a celestial globe, the profundity of any 
cluster marked in the figure is to be examined. This point, 
for the cluster VI, 7, is 58° 17' south-west, which denotes 
that the globe must be turned horizontally till the 58th 
degree of the south-west quadrant directly faces the observer, 
or that, by changing his situation, he must place himself so 
as to face the globe in the assigned position, 
I have called the construction of the figure which gives the 
profundity of the clusters, an artificial one ; because, as soon 
as the celestial globe is brought into the situation where it 
can be seen from the tabular point of sight, the figure will 
