44 PHYSIOLOGICAL AND PATHOLOGICAL 



When I come to treat of the physiological and 

 pathological laws of caloric, it will be found that 

 the aggregate amount of life on our planet is in 

 proportion to the heating power of the sun, ceteris 

 paribus : that no seed ever germinates, and no 



each of them is modified by the disturbing influence of all those 

 beyond, this also tends to alter the circular form of the orbits, 

 and render them more or less elliptical. Nor is it less ob- 

 vious, that the interference of the moon must cause a successive 

 diminution of gravity or sethereal pressure upon the earth, so as 

 to cause a corresponding elevation of the tides, which are still 

 further elevated by the influence of the sun when in conjunction 

 with the moon. Thus we perceive that as the mean temperature 

 of planets, (at least of the earth,) and of the spaces between 

 them, is uniformly the same, there must be a perpetual circula- 

 tion of caloric from and to the centre of the solar system, as from 

 and to the planets. We have also found that the heating power 

 of the sun is just equal to the centrifugal force of planets, and an 

 accurate equation of the gravitating force : from which it follows, 

 that whatever is true of the laws established by Kepler and New- 

 ton, must be equally true of the foregoing induction ; while it 

 has the additional advantage of assigning a well known principle 

 as the physical cause of the phenomena, and of thus affording 

 a resting place for the mind. 



From all the foregoing facts and observations we are authorized 

 to conclude, that caloric is a self active principle which is per- 

 petually circulating throughout the universe, from suns to 

 planets, and back again to the great fountains from which it 

 emanates : in short, that it is what Homer called 



" The golden everlasting chain, 

 Whose strong embrace holds heaven, and earth, and main." 



That the movements of the heavenly bodies are in some way 

 immediately dependent on the heating power of the sun, appears 

 to me almost a self-evident proposition, and was so regarded by 

 many of the ancient sages of the east. It was also vaguely re- 



