Mr. Groombridge’s Observations 
m 
solstices, have produced only eighteen observations at the 
summer, and thirteen at the winter, solstice. The proof re- 
sulting from this small number is, however, satisfactory; 
these being reduced to the same period, ist January, 1807, 
are as follow : 
App. zen. dis. Refraction. Correct. True zen. dis 
sum. sols. 27 0 59' 38/00 o' 29/83 -{- o" 85 28° o' 8/68 
winter do. 74 32 24,16 3 26,34 5,32 74 35 56,02 
102 56 470 
Latitude 51 28 2,35 
The mean obliquity of the ecliptic for the same period will be 
74° 55 56/02 
28 o 8,68 
46 55 47.34 
23 27 53,67 
The new solar tables state the obliquity of the ecliptic for 
1800 at 23 0 27' 57", and taking the decrease at half a second 
per annum, shews the above result to be very near the 
truth. 
I shall now compare the observations of Lieut. Col. Mudge, 
made at the Royal Observatory in 1802, with his zenith 
sector, to ascertain the difference of latitude between that 
place and my observatory : the following stars being reduced 
to the same epoch (2 y 45, 46, 51, Draconis ; jc, t, Cygni ; y, tj, 
Ursac majoris ; 1, Herculis, and Capella. The mean difference 
of the zenith distances of these stars, and my own observa- 
tions, is 35/49 ; which being added to my latitude, shews 
the latitude of the Royal Observatory to be 51 0 28' 37/59; 
