4 JOHN HAMILTON, M. D. 



St. Lawrence Bay, Asia, Lat. 65° 30'— Lon<;. 170° 44' 

 St. Matthew's Island, southeast point. Lat. 60° 18' — Long. 172° 4' 

 Tschunukttiu River, Kenai, enters Cook's Inlet, Lat. 61° 16' 

 Uualaschka, U. S. C. S. Stat., Lat. 53° 54'— Long. 166° 33' 

 Ungua Island, Coal Harbor, Lat. 55° 44'— Long. 160° 49' 



Regarding the earth as a sphere, each degree of hititude equals 

 69.5 statute miles. A degree of longitude on the equator is of the 

 same length, but each degree becomes shorter as an advance is made 

 towards either pole. As it is often desirable to know the length of 

 a degree of longitude on different parallels of latitude the following 

 table of approximate lengths may be useful : 



Lengtli on parallel of 25°, 62.988 statute miles. 

 30°, 60.189 

 35°, 56.922 

 40°, 53.239 

 45°, 49.144 

 50°. 44.764 

 55°, 39.854 

 60°, 34.750 

 65°, 29.371 

 70°, 23.770 

 75°, 17.988 

 80°, 12.058 

 85°, 6.058 

 89°, 1.213 



A knowledge of the length of the day at the Summer solstice may 

 be of use to the entomologist contemplating a trip to Alaska and the 

 latitude for each half hour's increase will be found in the subjoined 

 table. 



