APPENDIX. 447 



Fort St. Anthony - Dr. Edward Purcell, - Surgeon. 



Prairie du Chien - Dr. Charles Mendenhall,* Assistant Sui'geon. 



Gi'een Bay - - Dr. W. V. Wheaton, - Surgeon. 



Mackinac, (Mich.) - Dr. William Beaumont - Assistant Surgeon. 



Detroit, (Mich.) - Dr. B. Delavan, - - Surgeon. 



Fort Niagara, (N. Y.) Dr. William Ballard, - Assistant Surgeon. 



The mean temperature, &c. for Philadelphia, as recorded in 

 the Register, were furnished by Mr. Reuben Haines, Corres- 

 ponding Secretary of the Academy of Natural Sciences, Phila- 

 delphia, and Honorary member of the Royal Academy of 

 Sciences of Turin, whose judgment and precision in observa- 

 tions of this nature entitle them to the fullest confidence. 



It is believed that the foregoing tables exhibit as correct 

 statements in relation to the temperature of the several places 

 of observation, as any others that have hitherto been published 

 on a scale equally comprehensive. It is well known that me- 

 teorological observations of every description are liable to num- 

 berless inaccuracies, both from defects in the instruments 

 necessarily employed in making them, and from the want of a 

 uniform mode of observation. 



We are informed by the Surgeon General that the thermo- 

 meters used at the military posts were made by Mr. Fisher of 

 Philadelphia, who sustains a high reputation as a manufac- 

 turer of that instrument — and that they were uniformly fur- 

 nished with metalic scales, with the exception perhaps of some 

 few that have been procured to supply the place of those acci- 

 dentally broken. The observations from which the tempera- 

 ture as recorded in the tables, has been deduced, were taken 

 daily, at morning, mid-day, and evening, at which times the 

 state of the weather, wind, &c. were particularly noted. But as 

 it was not practicable to exhibit the whole in a form sufficiently 

 condensed, much interesting matter relative to atmospheric 

 phenomena, has necessarily been excluded from the register. 



* Deceased since 1822. 



