ON THE INTERACTION OF NATURAL FORCES. 173 



temperature produced by the condensation of the mass of the 

 sun, let us set 



we have then 



/= 



5. A. R. m. < 



For a mass of water equal to the sun we have a = 1 ; then 

 the calculation with the known values of A, M, R, m, and r, 

 gives 



t = 28611000 Cent. 



The mass of the sun is 738 times greater than that of all 

 th3 planets taken together; if, therefore, we desire to make the 

 water mass equal to that of the entire system, we must multiply 



738 



the value of t by the fraction - - - , which makes hardly a sensible 

 739 



alteration in the result. 



When a spherical mass of the radius R condenses more and 

 more to the radius R u the elevation of temperature thereby 

 produced is 



6' A . ma- 



R,) 



_ 

 6'AKjmo- I R ! 



Supposing, then, the mass of the planetary system to be at 

 the commencement, not a sphere of infinite radius, but limited, 

 say of the radius of the path of Neptune, which is six thousand 

 times greater than the radius of the sun, the magnitude 



T? 1 



-i will then be equal to .-77777., and the above value of t would 

 K 6000 



have to be diminished by this inconsiderable amount. 



From the same formula we can deduce that a diminution of 



