101 



Sunshine and elimate of Winnipeg — Continued. 



In the above table the records of sunshine are, of course, given by 

 the self-registering method and relate to duration of visibility of sun 

 at the station, Avhile the cloudiness is the average of the observer's 

 estimates of area of skv covered. 



TOTAL POSSIBLE DURATION OF SUNSHINE BY DECADES. 



Tables showing the times of sunrise and sunset, or the resulting 

 length of the day, are given is publications accessible to American 

 leaders, as follows: Meech, 1855, pages 57, 58, calculated especially 

 for the year 1853; Schott, 1870, pages 117-119, computed for an aver- 

 age year and for the actual sunrise and sunset and for each degree of 

 latitude; the Smithsonian Meteorological and Physical Tables, 

 fourth edition, 1884, give a very convenient table on pages 711-720, 

 by Prof. W. Libbey, computed with the declinations for Greenwich 

 mean noon for 1862 ; elaborate general tables are given in the Inter- 

 national Meteorological Tables, Paris, 1890, but they are not so conve- 

 nient for our use as the Smithsonian tables or those of Schott. 



By means of these tables of sunrise and sunset I have computed 

 the accompanying table, showing the sum total of the possible sunshine 

 expressed in hours from the beginning of January up to any date in 

 a. common year or a leap year." From this table has been made up 

 the column of maximum sunshine in the tables of meteorological 

 results for 1879 at twenty stations in the United States as given in 

 Section II for comparison with th# crops of that year, as reported in 

 the United States census for 1880.'' In the absence of anv other data 



" The annual sums for December .SI in the table are about one-third to on*^- 

 half per cent smaller than the figures given in the Weather Bureau table of 

 190.'. 



6 All these manuscrijtt statistical tables are omitted in the present etlitiou. 



