﻿26o ON THE ASTRONOMICAL COMPUTATIONS 



torial dimension 5059, to the dimension in Yojav.s 

 required. 



Of a variety of methods for finding the latitude of 

 a place, one is by an observation of the palabha, or 

 shadow, projected from a perpendicular Gnomon when 

 the sun is in the equator. The Sancu, or Gnomon, is 

 twelve anguhs, or digits, in length divided, each 

 into sixty v'mgulas ; and the shadow observed at 



A v 



Benares is 5, 45. Then, by the proportion of a 



A v 



right angled triangle V12. ^ + 5,45. — 13 18 the 

 acsha carna (hypotenuse) or distance from the top of 

 the Gnomon to the extremity of the shadow ; which 

 take as radius, and the projected shadow will be the 

 sine of the zenith distance, in this case, equal to the 



latkude of the place 3 438 ' X A ^ = 1487, the arc corre- 



13 18 

 s-ponding with which, in the canon of sines, is 25 26' 

 the latitude of Benares. The sine complement of 

 the latitude is 3101' 57", and again by trigonometry 



3101" 5/+5059 3S _^^ ^ Yogans the circumference 

 of a circle of longitude in the latitude of Benares. 



*D 



The longitude is directed to be found by observa- 

 tion of lunar eclipses calculated for the first meridian, 

 which the Surya Siddlmta describes as passing over 

 Lanca, Rohitaca, Avanti, and Sannihita-saras. Avanfi 

 is said by the commentator to be " now called Ujjay- 

 jni" or Ougehi, a place well known to the English in 

 the Mahratta dominions. The distance of Benares 

 from this meridian is said to be sixty-four Yojan cast- 

 ward ; and as 4565 Yojan, a circle of longitude at 

 ^Benares, is to sixty dandas, the natural day, so i3 



Danda Pala 



sixty-four > Yojan to o, 50, the difference of longi- 

 tude in time, which marks the time after midnight, 

 when, strictly speaking, the astronomical clay begins 



