420 



APPENDIX. 



By a diary kept at the garrison of Detroit (Fort Slielby), agree- 

 able to orders from the War Department, from the 15th of Nov. 

 1818, to the 28th of Feb. 1819, making 105 days, 



40 of them are marked "clear," 



40 "cloudy," 



13 " clear and cloudy," and 



12 " cloudy, with rain or snow." 

 By Fahrenheit's thermometer, kept at the same place, and under 

 the same direction, it appears that the medium temperature of 

 the atmosphere was agreeable to the following statement : — 



7 A. M. 



P. M. Average. Lowest deg. Highest deg 



Prevailing winds, S. W. and N. W. 

 Ohservations on Lake and River St. Clair, Michigan. 



Ohservations on Lake Huron. 



