62 WHAT IS LIFE? 



become liquid molecules liquid air. - Thus pressure, at 

 least an excess over the atmospheric pressure, is not 

 necessary to liquefy gases. Only deprive the gaseous 

 molecules of Ether, they pass into the liquid condition 

 and further deprive the liquid molecules of Ether, then 

 they become the solid molecules : illustration ice. 

 Although oxygen and nitrogen, the main constituents 

 of the air, are known by chemists to combine in five 

 proportions, in the case of liquid air there is no combina- 

 tion. 1 The molecules forming liquid air are all free, 

 and when evaporation takes place the nitrogen mole- 

 cules absorb Ether first and spring into the gaseous 

 form, followed by the residuum the oxygen molecules. 

 Experiment proves this. This shows a selective power 

 for Ether, or it may thus be expressed : There is a law 

 of the strongest amongst molecides in seizing Ether.* 



Now, although our diagram illustrates only one 

 species of molecule of three atoms or multiples of 

 three, which assumes different specific forms, combina- 

 tions of the same order, perhaps of hundreds of atoms 

 overwrapping each other and always in definite succes- 

 sion, may exist to produce a definite compound, a 

 molecule, even AN ORGANIC MOLECULE. In one order of 

 combination or configuration the molecule may be a 

 poison, in another order consisting of the same number 

 of atoms an antidote. 2 Hence the chemist's conception 



1 When a strong alternating current is passed through air - from 

 the two electrodes there is seen a flame the result of combining 

 oxygen and nitrogen. A gas is thus formed, of which little is known 

 at present. 



2 " Enough has been said to show that proteids are also protean, 

 and that they may offer many kinds of opportunities ' for different 

 kinds of chemical intercourse.' One kind of proteid maybe nutrient, 

 another may be poisonous, another may be protective from further 



* See Appendix, p. 287. 



