COSMIC PHILOSOPHY 



ciples of thermal radiation and conduction, of 

 evaporation and precipitation, condensation and 

 rarefaction. Biology was obliged to wait until 

 chemistry had thrown light upon the molecular 

 constitution of the various tissues and anatomi- 

 cal elements, and had furnished the means of 

 explaining synthetically such organic processes 

 as digestion and assimilation. But, as we have 

 already seen, the obligation has not been all on 

 one side. The services rendered by the analy- 

 tic to the synthetic sciences have been all along 

 repaid by services no less essential. Thus the 

 great principle of molar physics — the law of 

 gravitation — could not be generalized from 

 terrestrial phenomena alone, but had to wait 

 until astronomic observations had revealed the 

 true forms of the planetary orbits and the rates 

 of their velocities. Thus molecular physics has 

 received important hints from mineralogy, the 

 properties of crystals having rendered indispen- 

 sable aid in the discoveries of polarization and 

 double refraction, and therefore in the final ver- 

 ification of the undulatory theory. And thus 

 also in late years the researches of Dumas, Lau- 

 rent, Gerhardt, and Williamson on the struc- 

 ture of organic molecules have reacted upon the 

 whole domain of inorganic chemistry, regener- 

 ating the doctrine of types, supplying the fun- 

 damental conceptions of atomicity and quantiva- 

 lence, replacing the dualistic theory of Berzelius 

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