CONTENTS. 



Advertisement . 



SECTION I. 



General remarks and explanation of tabular results . . . . . . vii 



Special table of corrections for daily variation of temperature in each month and the year, for 



every hour and for various combinations of hours ...... xiv 



Tables of mean temperature for each month, season, and the year at various stations, principally 



in North America .......... i 



Graphical representation and explanation of the isothermal charts . . . .101 



Deductions from the charts of the distribution of the mean annual temperature, and of the 



distribution of the temperature during the winter and the summer seasons . . 104 



Illustrations to Section I. 



Chart of the United States showing the distribution of the mean annual temperature, by 



isothermal curves, drawn for every fourth degree (Fah.), from 36° to T6°. 

 Chart of the United States showing the distribution of the mean winter temperature (December, 



January, and February), by isocheimal curves, drawn for every fourth degree (Fah.), from 



4° to 12°. 

 Chart of the United States showing the distribution of the mean summer temperature (June, 



July, and August), by isotheral curves, drawn for every fourth degree (Fah.), from 56° to 88°. 

 (For explanation see page 101 and following.) 



SECTION II. 



Discussion of the daily fluctuation of the atmospheric temperature .... lOT 



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-hourly, hourly, and semi-hourly mean tem- 

 peratures for each month and the year . . • . . • .137 

 [For consolidated table of corrections for daily variation of temperature at four prin- 

 cipal 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 temperatere, 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 



Illitstrations to Section II. 

 Wood-cuts: Diagrams A and B, showing the daily variation, on the yearly average, for latitudes 



27° and 75°, and for 40° and 44° . , . . . . . . 156 



( iii ) 



