TABLE OF CONTENTS. xvii 



PAGE 



Section II. Discussion of the daily fluctuation of the atmospheric tempe- 

 rature . . ■ . . • • • .107 

 Times of sunrise and sunset in different latitudes, and for every tenth day 



in each month . . . . • • • .113 



Tables of bi-hourly, hourly, and semi-hourly mean temperatures, for each 



month and the year at various places in North America . . 121 



Tables of differences from the mean of the day, of bi-honrly, hourly, and 



semi-hourly mean temperatures for each month and the year . . 137 



[For consolidated table of corrections for daily variation of tempera- 

 ture at four principal stations, in each month and the year, for 

 every hour and for various combinations of hours, see page xiv.] 

 Systematic representation of the daily fluctuation of the temperature, by 



means of a periodic function . . . • • .153 



Analysis of the daily fluctuation . . • • .154 



Variability of the temperature at any hour of the day from the normal 



value of that hour ....■•• 162 



Section III. The annual fluctuation of the temperature expressed in terms 



of a periodic function ...•■• 169 

 Table of computed annual fluctuation of the temperature at 46 stations . 175 

 Discussion of the results for dates of mean annual values, and for maxima 

 and minima; and annual range in connection with the geographical dis- 

 tribution of the stations ...■•• 180 

 Examination into alleged interruption in the regularity of the annual 

 fluctuation at certain epochs, with tables of temperature of each day of 

 the year, deduced from a series of years .... 183 



Investigation of the variability of the temperature of any one day in a 

 series of years ....-..• 19'^ 



Inequality in the epoch of the minima and maxima of the annual fluctuation 199 

 Tables of observed extremes of temperatures, arranged by months, for a 

 selected number of stations ....■• 202 



Analysis of tabular results for greatest heat and greatest cold with r-egard 



to geographical distribution ...... 226 



Extreme annual range of temperature and monthly absolute variability, 



exhibition of the law of annual distribution .... 227 



Tables of the mean annual temperature, principally in the United States, 

 for a succession of years, from the earliest records to the close of the 

 year 1870 ........ 228 



Investigation of the secular variation of the annual mean temperature, and 



of the permanency of the climate ..... 302 



Comparison of the secular variation of the temperature with the variations 



in the frequency of the solar-spots ..... 314 



Comparison of the secular variation in the temperature and rain-fall in the 



United States . . . . ■ . .315 



Comparison of the secular variation in the temperature with the average 



annual direction of the wind ...... 316 



Range of variability in the secular variation of the annual temperature . 318 

 Secular variation in the annual minima and maxima, compared with the 



variation in the annual means . . . ■ • • 319 



List of Stations . . . . . ■ • • 321 



List of Observers .....-•■ 333 



Index ......••• 341 



