[ 4° 8 1 
XXX. Of the geographical situation of the Three Presidencies, 
Calcutta, Madras, and Bombay, in the East Indies. By J. 
Goldingham, Esq. F. R. S. 
Read June 27, 1822. 
In the present advanced state of knowledge it may be use- 
less to dwell upon the importance to navigation, as well as 
to general geography, of correct information relative to the 
latitudes and longitudes of the principal places on the surface 
of our globe. The ease with which the situation of a place on 
the meridian is obtained, for general purposes, is well known, 
and the comparative difficulty of ascertaining the distance, 
east or west, from a given meridian is equally so, particularly 
where that meridian is a quarter of the globe distant, which is 
the case as relates to India. Having, however, one point cor- 
rectly determined, the situations of others, at moderate dis- 
tances from it, may be come at with greater facility ; either 
by chronometers, by correspondent observations, or, where 
places are on the same continent, by actual survey. 
One of the best methods of determining the position of a 
point, thus distant from the first meridian, is by eclipses of 
the satellites of Jupiter. Correspondent observations of 
eclipses of the sun, of the moon, or of occultations, happen 
but seldom, and the method by the moon’s transit requires, 
that the position of that luminary should be correctly set 
down in the Tables ; or, in the case of correspondent transits, 
that the instruments at both places should be most accurately 
