4 86 An Account of the Measurement 
them, if I thought proper. His Grace was pleased to comply 
with my request ; and I now avail myself of the advantage pro- 
cured by that condescension. 
Blenheim Observatory. 
Zenith Distances of y Draconis, reduced to the Beginning of the 
Tear 1794, from Observations made in five successive Tears , by 
his Grace the Duke of Marlborough. 
From the observations of 1794, o° 19' 17", 32 y Draconis south of the 
1795 i7>7o zenith. 
179 6 17*51 
1 797 1748 
179 8 1 7 > 3 % 
Mean 0191 7,4 6. Therefore, the mean 
zenith distance of y Draconis, at Blenheim, on the 1st of January, 
1802, maybe taken at o° 19' 23", 06 south. The zenith dis- 
tance of this star, at the same period, at the station Dunnose, 
as derived from the late operation, is o° 53' 56", 63 north; 
therefore, o° 53' 56", 63 + o° 19' 23", o 6 = i° 13' 19", 69, is the 
difference of latitude between Dunnose and Blenheim observa- 
tory ; and here, perhaps, it may not be improper to advert to 
page 675 of the Phil. Trans, for 1800, where the observed and 
computed latitudes are given, the former being 3 1° 30' 24" 9, 
and the latter 51 0 30' 28'hi. The latitude of Dunnose is 
50° 37' 8", ai, that of Greenwich being taken at 51 0 28' 40"; 
and their difference o° 31' 31 ",39, as derived from the observa- 
tions made with the new sector. Hence, 50° 37' 8",2 j -j- 
1° 13' 19", 69 = 51 0 50' 27", 9, must be the latitude of Blenheim, 
within a small part of a second of the truth. But it will be 
improper to dwell on this matter at present ; and, therefore, l 
