#6 Mr. Bowditch on the solar eclipse, Sept. 17, 1811. 
In calculating the time of conjunction in this and in the following 
observations, the moon’s tabular longitude and latitude were first used 
without correction, and the time was found by calculation both for the 
beginning and end, the mean being taken for the time of conjunction. 
By repeating the process with those observations best adapted to the 
purpose it was found, that if the sun’s longitude as given by Delam- 
bre’s tables was correct, it would be necessary to decrease the moon’s 
longitude as given by Burg 12”-0, and to decrease the tabular latitude 
by 10’6. ‘The error in longitude was deduced from the obseryations 
at Sulem, and in latitude from those of N antucket, Monticello and 
Washington. Two micrometrical observations made at Nantucket 
near the middle of the eclipse, gave for the correction of latitude— 
9-2 and—12”-4, mean— 108; the observations of the internal con- 
tacts of the eclipse at Monticello gave - — 104, and those at Washing- 
ton — 10"°6. The mean of all these observations makes the error of 
latitude —10'*6. It may be observed that this correction makes but 
very little change in the calculated longitudes of the places of obser- 
vation, because the times of conjunction is affected in nearly the same 
way at most of the places. Thus, it was found that the correction of 
the time of conjunction at Salem, Brunswick, Portland, and Nantuck- 
et was 0"*8; at Burlington and Rutland+0"-9; at New Haven+410; 
at New Brunswick +171; at New York +13 ; at Washington +14; 
at Monticello+1":9, and at Williamsburg (where the first internal con- — 
tact was not observed) +.0’*3. Hence the corrections of longitude 
arising from this source are respectively 0”*0, 0’*1, 0-2, 03, 05, 
06, 11, and—0”5; most of which are so small as to be — 
worthy of notice. 
The error of the moon’s longitude — 12”-0 has no sensible effect — 
on the calculated longitudes from Greenwich, the time of conjunction 
being decreased about a quarter of a second at all the places of ¢ obser- 
vation mentioned in this memoir, 
eee LE SET Ree ay APS rey. ee eS ae. een eee 
