18 ECLIPSE OF THE SUN, NEAR OLMOS, PERU, 



we find 



For first internal contact. Second internal contact. 



o I II o I II 



If 2'+ T' represents the required time of the first meridian, at which a phase of 

 the echpse was observed, d the east longitude, and t the local mean time of ob- 

 servation 



First C. Second C. 



n sin 4' 



d = t—T-^ T' + hs + h2, tang ^ 



h = ~ = 1.8369 



2.06265 71 sin n 



, J f — .SOIOO for first int. contact, 



i + .08357 for second int. contact, 

 e =:^ sin N cos h A{a — a) + cos N A {h — d), 

 ^ = — cosN cos h A (a — a) + sin N A {h — d), 

 ^^ 08''41'" 8.83+ 1.8369 e — 0.30100 ^, 



( 18 41 8.05 + 1.8369 e + 0.08357 ^. 



The observations of the French officers furnish us with the following values: — 

 Approximate longitude = 80° 59' 40" 

 Geocentric latitude = — 5 47 40 



19'' 24"° 8' first internal contact, 



19 25 7 second internal contact. 



Computing as before, we obtain the following values for the east longitude of 

 their station from the Greenwich meridian: — 



^,_ ( 18'' 35°' 53\89 + 1.837 e — 0.483 ^, 

 ~ ( 18 35 54.76 + 1.837 s + 0.284 I. 

 Therefore, 



d — d'= 5 ^" 14.94+ .182 ^, 

 ^5 13.29— .200 i. 

 As no observations were made at a station whose longitude was known, the 

 values of 2, and e cannot be determined. 



