2 6 a Mifcelhnea Curtofa. 



I fore-fee St will be Obje&ed, that I take the 

 Radius of my Circle on which I ere& my Per- 

 pendiculars always the fame, whereas the Paral- 

 lels of Declination are unequal; but to this I 

 anfwer, That our faid Circular Bafes ought not 

 to be Analogous to the Parallels, but to the 

 Times of Revolution, which are equal in all of 

 them. 



It may perhaps be ufeful to give an Example 

 of the Computation of this Rule, which may 

 feem difficult to fbme. Let the Solfticical Heat 

 in S and Y? be required at London, Lat. $i° 



380-2' 8 Co- lat. 



23 ^30 Dech ® 



61 -58 Sinus— ,8826 4 



14 -58 Sinusal f 2$Z%2 

 Summn 1,140931 

 Diff. ,624417 



Dijf. Afcen. 3300-1' u 

 Ahb.Semid. afiiv. 123 -11. 



4r.Sem.kyb. 56-49.S.638923 

 Arc. hyh. jnenfura, 9916%$ 



Then I ,140931 in ,836913, 4- 6x4417 in % 

 ,1499^5'— * ^9734- And 1,140931 in 836919 

 —,614417 in ^99 I ^3 8 = 33 8 95T- 



So that 1,19734 will be as the 'Tropical 

 Summers Day Heat, and 0,33895" as the 

 Action of the Sun in the Day of the Winter 

 Soiftice. 



After this manner I computed the following 

 Table for every tenth Degree of Latitude, to 

 the j&qumocYial and Tropical Sun, by which 

 an Eftimate may be made of the intermediate 

 Degrees, 



Lat. 



