Sun-spot Areas and Diurnal Temperature- Ranges. 301 



Results of Comparison of Inequalities around 24 Days. 



15. Comparison in Length of Period. The comparative magnitudes 

 of the various solar Inequalities, whether apparent or real, are, as we 

 have already explained, estimated by adding together the various 

 yearly results appropriately placed, and then in the final Inequality 

 so obtained by summing up the various departures whether positive 

 or negative. The result for sun-spots is given in the form of a sum 

 consisting of four or five places. Of these we may to save space and 

 time dismiss the two right hand figures, that is to say, divide by 100, 

 while yet retaining a result sufficiently accurate for the purposes of 

 our comparison. We have made this reduction in the following table 

 not merely for sun-spots, but likewise for temperature-ranges. It has 

 to" be remembered that for siin-spots and Toronto temperature-ranges 

 the results exhibit the sum of 36 years, while for Kew temperature- 

 ranges they only exhibit the sum of 24 years. The Kew temperature- 

 ranges are esteemed by us to be of subordinate value, partly because 

 they consist of a smaller number of years, and partly because they 

 have only 12 years in common with- sun-spots, and they have been 

 here introduced for a reason that will afterwards appear. Meanwhile 

 in our comparison as to length of period we confine ourselves to sun- 

 spots and Toronto temperature-ranges, inasmuch as each of these 

 series embodies 36 years, of which 24 years are common to both. 



In the following table we have inclosed in brackets the positions of 

 all sufficiently well-defined maximum Inequalities, whether of sun- 

 spots or Toronto temperature-ranges. We have likewise given a list 

 of the Kew temperature-range Inequalities, but for the reason already 

 mentioned we have not used these for the purpose of comparison, and 

 have not inclosed their maximum points in brackets. 



