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computed by their geometry the angle which the gnomon 
makes with the line drawn from its top to the extremity 
of the shadow. The longitude is directed to be found by 
observations of lunar eclipses, calculated for the meridian 
of Lanca, which passes through Oujein, one of their most 
ancient cities. The obliquity of the ecliptic they consi- 
dered equal to 24° (the Chinese also state it to be 24°, but 
from their dividing the circle into 365£°, this is only equal 
to 23° 39'.) The precession of the equinoxes they reckoned 
equal to fifty-four seconds in a year, but it is actually 
four seconds less than they supposed. 
Though it is difficult to prove, whether or not, the Indians 
were indebted to the Greeks for any of their principal 
determinations, Mr. Davis and Delambre, both opposed to 
the great antiquity of the Hindoo astronomy, think their 
methods of calculation essentially different from the Grecian, 
and that those for eclipses, though tedious, are curious, 
and bear the appearance of originality. One of the most 
striking instances of this, is the method given in the tables 
of Chrisnabouram, for finding the time of the sun's conti- 
nuance above the horizon, or what is called the diurnal 
arc for any given day. From the rule given not being 
rigorously true, and the differences between the supposition 
of the Brahmins and the exact formula, being very appre- 
ciable in high, but inconsiderable in tropical latitudes ; 
it is evident that the rule which they adopt must have 
had its origin in a tropical country ; and in all probability 
in the Indian Peninsula where it is found. (Playfair.) 
Among the objections made to Hindoo astronomy, there 
is one which I think susceptible of explanation ; and 
that is, their want of instruments, or modes of making 
observations. To this it may be replied, that in the Vishnu 
Dhermotter, it is directed that the planets be observed 
with an instrument : and in their method for determining 
