140 



PHILOSOPHICAL TRANSACTIONS. 



[anno 1786. 

 16'. The place of observation was in Botham, about 400 



the lunar eclipse 4 



or 500 yards N. W. of York Minster. 



Part of the Eclipse of the Moon, Sept. 10, 1783. 



The two last Columns show the difference of Meridians between Greenwich 



and York. The observations marked with an asterisk were made by Mr. 

 Goodricke. 



Spots observed. 



Ga] ileus bisected 



Aristarchus covered. . . , 



Copernicus touches . . . . < 



Copernicus bisected . . . . -j 



Copernicus covered .... 



Plato touches 



Plato covered 



Manilius touches < 



Tycho touches i 



Manilius covered 



Tycho covered -j 



Menelaus bisected .... 

 Prom . Acut. Cen. covered 

 Proclus bisected 



Mare Crisium touches . . -j 



Mare Crisium bisected. . 

 Mare Crisium covered. . 

 Grimaldus emerges .... 

 Grimaldus bisected .... 



Grimaldus emerged . . . . -j 



Galileus emerges 



Galileus bisected 



Aristarchus bisected. . . 



York, by Mr 



Goodricke and 



me. 



App. time. 



9 45 32 

 9 49 13* 

 9 57 3* 

 9 57 20 

 9 58 33* 

 9 58 55 

 9 59 

 5 

 6 



10 11 

 10 11 



13 32 

 15 41 



9* 



7 

 18 

 26* 

 33 



10 11 57* 

 10 11 57 



10 12 47* 



10 13 8* 



10 



10 



10 25 26* 



10 29 00 



10 30 18* 

 10 30 18 

 10 32 43* 

 10 35 38* 

 12 23 30 

 12 23 44- 

 12 23 55* 

 12 23 59 

 12 25 50* 

 12 25 56* 

 12 28 59 



Paris, by M. 

 Mechain. 



App. time. 



h. 



9 

 10 



10 11 

 10 11 

 10 12 



58 33 



2 38 



18 



18 



5 



10 12 5 

 10 12 57 

 10 18 37 

 1') 19 52 

 10 25 34 

 10 25 34 

 10 25 34 

 10 25 34 



10 26 29 



10 27 19 

 10 27 19 



10 29 Ip 



10 39 5 

 10 42 28 

 10 43 56 

 10 43 56 

 10 46 34 

 10 49 11 



12 36 48 

 12 37 25 

 12 37 25 



12 39 16 

 12 43 8 



Paris, by M. 

 Messier. 



App. time. 



h. 



10 11 

 10 11 



10 12 41 

 10 18 40 

 10 19 28 

 10 25 24 

 10 25 24 

 10 25 24 

 10 25 24 

 10 26 53 

 10 27 8 

 10 27 8 



10 44 00 

 10 44 00 

 10 46 10 



12 37 5 



12 39 1 



Difference of meridians on a mean 4' 1 6" 



M. Mechain's Observatory was 9' 23", and M. Messier's 9 18" east of Greenwich. 



Mr. P. thinks the meridian observations of the moon's limb the best method 

 for determining the difference of meridians. The rule he adopted is this : The 

 increase of the moon's r.a. in 12 hours, or any given time, found by computa- 

 tion, is to 12 hours, as the increase of the moon's r.a. between two places, found 

 by observations, is to the difference of meridians. Instead of computing the 



