X90 SOME ACCOUNT OF THE 



are consequently radii of the arcs ; and from the points 

 on the upper edge of the gnomon where thefe lines 

 cut it, are conitructed two lines of tangents, one to 

 the northward, and another to the fouthward, to a 

 radius equal to that of the arc. To rind the fun's de- 

 cimation, place a pin among thefe di virions, perpen- 

 dicular to the edge of the gnomon ; and move it 

 backwards and forwards, till its fhadow falls on the 

 north or fouth edge of the arc below : the divi- 

 iion on which the pin is then placed, will fhew the 

 fun's declination. In like manner, to find the decli- 

 nation (kranti) of a ftar, and its d ftance in time, 

 from the meridian (net -gharry) place your eye among 

 the divilions of the arc, and move it till the edge of 

 the gnomon cut the ftar, while an aiiiitant holds a 

 pin among the divilions on the edge of the gnomon, 

 lb that the pin may feem to cover the ftar. Then 

 the divilion on the arc at which the eye was placed, 

 will fhew the diftance of the liar from the meridian ; 

 while the place of .the pin, in the line of tangents, 

 will fhew its declination. 



At Matra the remains of the obfervatory are in the 

 fort, which was built by Juyajlnha on the bank of the" 

 Jumna. The inftruments are on the roof of one of 

 the apartments. They are all imperfect, and in ge- 

 neral of frnall dimensions, 



1. An Equinoctial Dial, being a circle nine feet 

 two inches in diameter, placed parallel to the plane 

 of the equator, and facing northwards. It is divided 

 into gyhurries of lix degrees each : each of thefe is 

 fubdivided into degree-, which are numbered as puis 

 10, 20, 80, 40, 50, 60 : lattly, each fubdiviiion is 

 farther divided into rive parts, being 12 minutes, or 

 vmofuk. In the centre is the remains of the iron 

 ft) lc, or pin, which ferved to call the ihadovv. 



2. On 



