1906.] 



NATURAL SCIENCES OF PHILADELPHIA. 



569 



and effect may be obtained. Upon the completion of the railway 

 records were started, and have been kept with more or less regularity, 

 of the snowfall at three points near the summit of Roger's Pass on the 

 western slope of the Selkirk Range. While of course great variations 

 have taken place and inaccuracies have crept in, the summaries of 

 daily measurements are here given as they have been preserved for 

 three stations, "Cut Bank," at an elevation of about 4,000 feet, 

 Glacier House, 4,120 feet, and "No. 18 Shed," 4,300 feet. 



Table Showing Yearly Snowfall on West Slope of Selkirk Range. 



Year. 



1886-1887 

 1887-1888 

 1888-1889. 

 1889-1890 

 1890-1891 

 1891-1892 

 1892-1893 

 1893-1894 

 1894-1895 

 1895-1896 

 1896-1897 

 1897-1898 

 1898-1899 

 1899-1900 

 1900-1901 

 1901-1902 

 1902-1903 

 1903-1904 

 1904-1905 

 1905-1906 



Taking into account only the years in which records have been pre- 

 served gives the average snowfall at "Cut Bank," 19 feet 3 inches, 

 Glacier House, 30 feet 10 inches, and "No. 18 Shed," 33 feet 8 inches, 

 while the average yearly snowfall, taking into account all years ob- 

 served since the winter of 1886, gives 27 feet 11 inches. On the higher 

 slopes and the neve regions of the glaciers in the vicinity the snowball is 

 much greater, yet the above may be taken fairly as an average for the 

 elevation of Glacier House, 4,120 feet, or a little below the tongue of 

 the Illecillewaet Glacier. 



In the following pages no attempt will be made to describe the pecu- 

 liar phenomena of the several glaciers upon which measurements have 

 been made, but to briefly outline the observations made during 

 the last two weeks of July, 1906, together with sufficient description of 

 the work which has gone before to provide data for comparisons. 



