ASTRONOMICAL LABOURS OP JAYASINHA. 1^9 



thread perpendicular to the horizon ; but no mention 

 is made of this in the original defcription. 



5. Ndree-ivila-yunter, or equinoctial dial, is a cy- 

 linder, placed with its axis horizontally, in the north 

 and fouth line, and cut obliquely at the two ends, lb 

 that thefe ends are parallel to the equator (Ndree- 

 wilaj. On each of thefe ends a circle is defcribed^ 

 the diameter of which in this inftrument is 3 feet 7 

 inches and a half. Thefe are divided into gjiiirrles % 

 of fix degrees, into degrees and fubdivifions, which 

 are now effaced. In the centre of each circle, was 

 an iron pin (now wanting) perpendicular to the plane 

 of the circle, and confequently parallel to the earth's 

 axis. When the fun is in the fouthern figns, the 

 hours are ihewn by the fhadow of the pin in the 

 fouth, and when he is in the northern iigns by that 

 to the north. On the meridian line on both fides 

 are marked the co-tangent, to a radius equal to the 

 length of the centre pin. The fhadow of the pin 

 on this line at noon, points out the fun's declina- 

 tion. 



6. Semrdt-yiinter, alfo called Ndree-wila, another 

 form of equinoctial dial. (Fig. A of Sir Robert Bar- 

 ker's plate.) It conlifts of a gnomon of ftone, con- 

 taining within it a itair. Its length is 43 feet 3.3 

 inches ; height from the ground, at the fouth end, 

 3 feet 9.7 inches ; at the north end 22 feet, being 

 here broken. On each lide is built an arc of a circle, 

 parallel to the equator, of go degrees. Its radius is 

 9 feet 1 inch ; breadth from north to fouth 3 feet 1 

 inch. Thefe arcs are divided into gjmrries and fub- 

 divifions ; and the fhadow of the gnomon among 

 them points out the hours. From the north and 

 fouth extremities of the interfection of thefe arcs 

 with the gnomon, are drawn lines upon the gnomon, 

 perpendicular to the line of their interfection. Thefe 



are 



