xviii Introduction to the Makerstoun Observations, 1845 and 1846. 



Table 1. — Determinations of the Value of Angle A. 



Date. 



Readings of Horizontal Circle 



k 





For Wire of Declination Telescope. 



For North Mark. 



































Aagie A. 1 









Verniers 















Verniers 





























Mean. | 















Mean. | 









A. 



B. 





C. 







A. 



B. 





C. 











1844. 



/ 



n 



' 



// 



/ 



II 



o 



/ II 



f 



// 



/ 



ff 



' 



II 



o 



/ // 







/ // 



Feb. 7 



53 



17-5 



53 



21-5 



53 



57-5 



233 



53 32-2 



44 



12-5 



43 



52-5 



43 



57-5 



77 44 0-8 



23 



50 28-6 



May 11 



52 



2-5 



51 



52-5 



52 



8-7 



53 



52 1-2 



42 



2-5 



42 



22-5 



42 



42-5 



257 



42 22-5 



23 



50 21-3 



July 4 



52 



230 



52 



8-0 



52 



43-0 



53 



52 24-7 



42 



35-0 



42 



52-5 



43 



100 



257 



42 52-5 



23 



50 27-8 



July 22 



52 



10-0 



52 



00 



52 



25-0 



53 



52 11-7 



42 



27-5 



42 



51-2 



43 



2-5 



257 



42 47-1 



23 



50 35-4 



Aug. 14 



52 



40-0 



52 



18-7 



52 



46-2 



53 



52 350 



42 



400 



43 



00 



43 



20-0 



257 



43 0-0 



23 



50 250 



Aug. 14 



52 



35-0 



52 



7-5 



52 



47-5 



53 



52 300 



42 



400 



43 



1-2 



43 



25-0 



257 



43 2-1 



23 



50 321 



Aug. 14 



53 



15-0 



52 



57-5 



53 



20-0 



53 



53 10-8 



43 



23-7 



43 



52-5 



44 



50 



257 



43 47-1 



23 



50 36-3 



Aug. 14 



52 



55-0 



52 



51-2 



53 



37-5 



233 



53 7-9 



43 



15-0 



43 



2-5 



43 



10-0 



77 



43 9-2 



23 



50 1-3 



Aug. 14 



53 



5-0 



52 



54-0 



53 



17-5 



53 



53 5-5 



43 



22-5 



43 



51-0 



44 



2-5 



257 



43 45-3 



23 



50 39-8 



Oct. 14 



52 



250 



52 



28-7 



53 



150 



233 



52 42-9 



43 



100 



42 



47-5 



43 



5-0 



77 



43 0-8 



23 



50 17-9 



Oct. 14 



52 



27-5 



52 



28-7 



53 



12-5 



233 



52 42-9 



43 



7-5 



42 



400 



42 



57-5 



77 



42 55-0 



23 



50 121 



Oct. 14 



52 



38-7 



52 



17-5 



53 



0-0 



53 



52 38-7 



42 



37-5 



42 



57-5 



43 



25-0 



257 



43 0-0 



23 



50 21-3 



Oct. 14 



52 



46-2 



52 



22-5 



52 



58-8 



53 



52 42-5 



42 



43-7 



43 



0-0 



43 



250 



257 



43 2-9 



23 



50 20-4 



Oct. 19 



52 



11-2 



52 



13-7 



52 



58-8 



233 



52 27-9 



42 



57-5 



42 



36-2 



42 



55-0 



77 



42 49-6 



23 



50 21-7 



Oct. 19 



52 



32-5 



52 



7-5 



52 



43-6 



53 



52 27-9 



42 



52-5 



42 



56-2 



43 



16-3 



257 



53 1-7 



23 



50 23-8 



Oct. 19 



52 



450 



52 



16-2 



52 



52-5 



53 



52 37-9 



42 



40-0 



42 



57-5 



43 



25-0 



257 



43 0-8 



23 



50 22-9 



Oct. 19 



52 



41-2 



52 



350 



53 



20-0 



233 



52 52- 1 



43 



25-0 



42 



57-5 



43 



100 



77 



43 10-8 



23 



50 18-7 



Dec. 31 



52 



43-7 



52 



22-5 



52 



52-5 



53 



52 39-6 



42 



52-5 



43 



13-7 



43 



35-0 



257 



43 13-7 



23 



50 34-1 



Dec. 31 



52 



17-5 



52 



20-0 



53 



50 



233 



52 34-2 



43 



12-5 



42 



47-5 



43 



3-7 



77 



43 1-2 



23 



50 270 



1845. 







































Jan. 17 



52 



13-7 



52 



18-8 



52 



55-0 



233 



52 29-2 



42 



52-5 



42 



35-0 



42 



52-5 



77 



42 46-7 



23 



50 17-5 



Jan. 17 



52 



150 



52 



18-7 



52 



59-0 



233 



52 30-9 



42 



58-1 



42 



35-0 



42 



53-7 



77 



42 48-9 



23 



50 18-0 



Jan. 17 



52 



42-5 



52 



20-0 



52 



57-5 



53 



52 40-0 



42 



55-0 



43 



17-5 



43 



37-5 



257 



43 16-7 



23 



50 36-7 



Jan. 17 



52 



8-7 



52 



10-0 



52 



52-5 



233 



52 23-4 



43 



0-0 



42 



40-0 



42 



57-5 



77 



42 52-5 



23 



50 291 



Jan. 17 



52 



25-0 



52 



2-5 



52 



37-5 



233 



52 21-7 



42 



25-0 



42 



42-5 



43 



2-5 



77 



42 43-3 



23 



50 21-6 



Jan. 17 



52 



23-7 



52 



2-5 



52 



43-1 



53 



52 23- 1 



42 



38-7 



42 



55-0 



43 



15-5 



257 



42 56-4 



23 



50 33-3 



May 8 



52 



7-5 



52 



5-0 



52 



57-5 



233 



52 23-3 



43 



7-5 



42 



42-5 



43 



10-0 



77 



43 0-0 



23 



50 36-7 



1846. 







































Apr. 13 



48 



5-0 



47 



43-7 



47 



32-5 



53 



47 47-1 



37 



57-5 



38 



20-0 



38 



2-5 



257 



38 6-7 



23 



50 19-6 



Apr. 13 



47 



28-7 



47 



8-8 



47 



32-5 



233 



47 23-3 



38 



12-5 



37 



40-0 



37 



25-0 



77 



37 35-8 



23 



50 12-5 



May 7 



48 



5-0 



47 



33-7 



47 



27-5 



53 



47 421 



38 



2-5 



38 



22-5 



38 



5-0 



257 



38 10-0 



23 



50 27-9 



May 9 



47 



53-7 



47 



41-2 



48 



50 



233 



47 53-3 



38 



43-7 



38 



50 



37 



45-0 



77 



38 11.2 



23 



50 17-9 



May 9 



48 



17-5 



47 



200 



47 



200 



53 



47 39-2 



37 



55-0 



38 



10-0 



37 



57-5 



257 



38 0-8 



23 



50 21-6 



17. The mean value of angle A from all the observations 

 in 1844, 1845, and 1846, .... 

 The mean value of angle A from all the observations 



V- 



23° 50' 24"-5 



=23° 50' 23"-9 



in 1844, 



The value of angle Z (Table 8, Introduction, 1841-2), = V 37' 38"-8 

 Whence angle A + Z, =25° 28' 2"-7 



The absolute westerly declination, therefore, corresponding to the zeros of the 

 scales. No. 8, =25° 28'*04. This value has also been employed for the observa- 

 tions in 1845 and 1846. For other scale readings differing from the zero by the 

 angular quantity ± D, the declination is obtained from the formula, declination 

 = 25° 28'-04 =fc D. 



