at Leith Fort every Hour of the Day in 1824 and 1825. 



From the general character of the year 1825, these results, 

 as might have been expected, present greater uniformity in that 

 year than they do in 1824, or even in the mean of the two years. 

 The mean range is nearly at its maximum about the winter sol- 

 stice, and gradually increases till April, when it reaches its maxi- 

 mum. It then declines, and again rises to a second maximum 

 in July, after which it gradually diminishes till the end of the 

 season. The mean range for the year is 6.065, and does not 

 vary above the 100th part of a degree in 1824 and 1825. 



V. On the Parabolic form of the different branches of the Mean 



annual Daily Curve. 



Before concluding this Report, I was desirous of ascertaining 

 if the different branches of the daily curve had a resemblance to 

 any known curve. Their similarity to the parabola is very ob- 

 vious, from Fig. 2. of Plate XIV. where they are distinctly pro- 

 jected ; and I therefore calculated the following Table, upon the 

 supposition that AB, BC, CD, and DE, were parabolic branches 

 of the following dimensions : 



The ordinates 513 -f- 253 + 347 -f 327 are ~ 1440^ ~ 24 

 hours ; and the abscissa BH 2.872, and DG = 3.266; when 

 reduced to the same scale as that of the ordinates, become 1 72 



3 c 2 



