26 Observations on the eclipse of the sun, une 16, 1806. 
two numbers ; that is, by 1 115. So that this error of 60” in the du- 
ration would only cause an error ‘of 1” 15 in the latitude. By a simi- 
lar calculation the mean time of the least apparent distance of the cen- 
tres of the sun and moon at Nashewena was 11h. 27'57. The D s 
parallax—9’ s parallax, in longitude +5’ 34-01, in latitude—18’50”°68, | 
the moon’s apparent semidiameter 16’ 41’-51. Hence the least appa- 
rent distance of the centres of the sun and moon by the tables corrected 
as above was 61-34, the apparent difference of the semidiameters 
was 59”-01 : the difference, 2"-3, being added. to 68, gives 
nearly the limit of the correction of latitude —9” ‘1. That is, the cor- 
rection to be subtracted from the latitude given by the tables must. be 
se Ase 2. 1. pecause ‘a atte did not apport to be total. This 
2 ae 
ion 'at Rt eee pets _ gr. = 
Mr. Leslie also informed me that the eclipse v was observed at Pee 
tha’s Vineyard by several persons on the point called West-Chop, 
about half a mile from the extremity of the point, at which place the 
total darkness continued about a minute ; and at the distance of a mile 
and a quarter south of this place the eclipse was not total. By the 
above charts the latitude of the former point is 41° 28’ 10” N (reduced 
Al® 16' 47"); the latter 41° 26’ 55” N (reduced 41° 15’ 32”); and the 
longitude 4h. 42m. 16s. W from Greenwich. From these data I 
found, by calculations similar to the foregoing, that the mean time of 
the least apparent distance of the sun and moon was at 11h. 29m. 37s ; 
and at the first place the >’s parallax—®’s parallax in longitude ' was 
+5" 14""-32, in latitude —18' 50".31; the moon’s apparent semidiame- 
ter 16’ 41’54, the apparent motion of the moon from the sun in half a 
minute of time 11:58, and the apparent difference of the semidiame- 
ters of the sun and moon 59”°04. Hence, if the duration of total 
darkness was one: minute, the least distance of the centres of the sun 
and moon would be ¥59°04\*—11°58)’=57"-89. The distance at 
