98 Mr. Ivory on the Theory of the Astronomical Refractions. 



Example I. 



6 = 86» 14' 42" 



Therm. 8°-75 cent. = 47''-75F. 



Barom. 0"i-74l = 29-17 in. 



Example 2. 

 6 = 86° 15' 20" 

 Therm. 8i° cent. = 46°-9F. 

 Barom. 0™-766 = 30-16 in. 



Example 3. 

 Mean of 42 sub-polar observations 

 of « Lyrse by Dr. Brinkley. 

 Irish Transactions, 1815. 

 & = 87° 42' 10" 

 Therm. 35° 

 Barom. 29-5 



86° 



10' 



4 42" 



-2J 

 -8 



iction 

 ction 



2-86345 

 664 



86° 10' 

 5 20" 



Therm 



Barom 



LogS^ 



Id 



- -25 X -3-1 



- -4 X - -16 



Corrected refraction 

 Observed refraction 



2-86345 

 753 



Therm. 

 Barom. 



2-87009 



•00214 



9-98781 



2-87098 

 •00276 

 •00232 



Log§^ 

 Id 



-•25x - 

 •4 X 



2-86004 



724-5 



+ •5 

 — -3 



2-87606 

 751-7 



+ •8 

 + •6 



Corrected refn 



Observed refra 



12'4"^7 

 12 4 -2 



12' 33"- 1 

 12 32 -5 



87° 40' 

 2 10" 



Therm. 

 Barom. 



Log Id 

 Id 



— -6 X -15 



- M3 X i 



Corrected refraction 

 Observed refraction 



3-00522 

 392 



3-00914 



•01444 



9-99270 



3-01628 



1038"-2 



+ 9-0 



-0-6 



17' 26"-6 

 17 26 -5 



Example 4. 

 Mean of 10 observations of Ca- 

 pella, from a memoir of M. Plana. 

 Acad, de Turin, torn. 32. 



d = 88° 24' 9"-7 

 Therm. 47°-75 

 Barom. 29-75 



88° 20' 3-08087 



4 9*'-4 847 



Therm. 

 Barom. 



Log ^ d 

 Id 



— -95 X - 24 



- 1-6 X -27 



Corrected refraction 

 Observed refraction 



3-08934 



•00214 



9-99607 



308765 



1223"-3 



+ 2-1 



-0-4 



20' 25" 

 20 24 -3 



We may now inquire how far the refractions are hkely to 

 be affected by the term which it was found necessary to leave 

 out, because the present state of our knowledge of the phee- 

 noraena of the atmosphere made it impossible to determine 

 the coefficient^' by which it is multiplied. For this purpose 

 the term alluded to, viz. 



smfi xf'x -^7=^ X Q3, 

 V 5i 



