428 Prof. Kupffer 07J the Mean Temperature of Silka, in America. 



Table containing the Maxima and Minima of the Barometric 

 Height atid Temperature for each Month of the Year 1 828 

 (Old Style). 



If we take for Jloulouk the mean of the maxima and minima 

 of the barometric heights of all the months of the year 1828 

 (see the second table of the following article), we shall find 



Engl. Inches. 



Mean of maxima for Jloulouk 2992 



Mean of minima 28-80 



Mean 29-36 



To which, adding 0*32 ; that is to say, the error 



of thebarometer, which gave the preceding means, — Inches. 



we have 29*68. 



If we make the same calculation for Sitka, we shall 



obtain 29-68. 



That is to say, exactly the same value. This agreement gives 

 a greater weight to the observations than might otherwise be 

 attributed to them. 



It is easily seen that for Jloulouk the mean of the maxima 

 and minima of all the months is greatly different from the true 

 mean barometric height. 



With regard to the therm ometrical observations, we know 

 also that the mean temperature of the year does not differ 

 much from the mean of the maxima and minima of all the 

 months. 



The mean of these maxima and minima for Sitka, for the 

 year 1828, as we see by the preceding table, is -|-5°'8 Keaum, 

 or, 45°-05 Fahr. 



It is not, however, without diffidence that I communicate 

 this result. 



