(150) 
AL pee. 8 oe 
Aftronomical.Obfervations, Communicated by Davip Rit= 
TeNHOUSE. 
Obfervations of a lunar Eclip/e, Nov. 2d, 1789, and of the 
tranfit of Mercury over the Sun’s difk. Nov. 5thihe Jame 
year, made at the Univerfity of Wilham aud Mary, By 
the Revd Dr. JAMES Mapitson. 
Read Feb. AQ S the obfervatory in which the tranit‘infru- 
4 TOK: ment had:been formerly placed, was not, at 
this time, rebuilt, L was not euabled to attend to the going 
of the time-keeper, by means of iuch obferwations as I 
wwifhed to have made. 1 therefore had recourfe to corre- 
fpondent double altitudes, taken with a fextant. In tak- 
ing them, treacle was ufed, which not only gavea well 
defined image of the fun, but was of fufheient confiftency 
to prevent undulation, efpecially.as the obfervations were 
made in a room, where the wind -could have but little 
effet. From the great care employed, I think the time 
and rate of the clack were known with very confiderable 
accuracy. 
Nov. 2d, A-mean of the correfponding altitudes taken 
this day, made the clock 17’, 17” flower than apparent 
time; to which 9”! being added for change of declinati- 
on in the ‘half interval, hence the clock was flow of the 
fun, - ~ - 17. 20" 2018 
Obfervations of the lunar Eclipfe. 
* SEP. Ther 
Penumbra--thought to touch the» at 6 8 46 
Eclipfe begins, - - - 6 21.+0 
Tycho begins to immerge - 6 38 45 
wholly immerged = 43 ) lg 
Shadow 
