1814.] and on Vegetation. Si 



I made a delineation of these observations upon paper as the 

 abscissae and ordinates of a curve, and determined from the curve 

 the mean temperature of each month. From these means, the 

 medium for the whole year, as stated above, was deduced. It 

 agrees pretty nearly with the mean temperature of the atmosphere; 

 but stands accidentally almost two degrees lower than the constant 

 temperature of the springs at Upsala. As during the months of 

 April and May this spring was remarkably colder than the air, so its 

 higher temperature was equally conspicuous during the first winter 

 months ; and the final result shows that even a spring, which 

 changes in its temperature in so extraordinary a manner as this, still 

 deviates very little from the mean temperature of the air. 



That this difference from the temperature of the air increases in 

 proportion as the temperature of the springs becomes more constant, 

 may be learned from the following observations. 



The Professor spring, at Haga, varies in its temperature only 

 half as much as the preceding spring. I found it — 



1809— 5 November 45-50° 1810—18 April 38-57° 



11 45-14 1 May 38-30 



20 44*14 6 38-48 



29 43-88 10 38-48 



6 December 43-16 18 38*48 



25 41-54 25 39-02 



1810— 4 January. . 41*54 30 39-33 



17 41-54 6 June 39 92 



27 41-13 .10 40-37 



8 February. 40-2S 17 40-82 



12 40-46 25 August.. 46*04 



22 40*46 I September 46*04 



6 March . . . 40*10 25 4676 



16 39-74 2 October. . 46-76 



28 39-^9 12 46-49 



7 April 38-48 25 45*86 



Mean of the whole year 42*26° 



The mean temperature of this spring is higher than that of the 

 preceding, almost in the same proportion as its differences of tempe- 

 rature arc less. In both springs the rate of the variations is nearly 

 similar. 



Another spring, situated in the same district as the Professor 

 spring, and lying north-west from it, is still more constant in its 

 temperature. 1 found its heat as follows .- — 



1809—13 December 43*S8° 1810— 6 May 42-08° 



25 43-88 30 42-08 



1810—27 January.. 43*52 27 August .. 43-16 



7 February. 43*34 25 September 43*88 



-' i April . .'. . 4l'-OS 



Mean 42-98° 



