THE BREATH OF LIFE 



or agitation, much more intense, is supposed to be 

 taking place; the atoms which compose the mole- 

 cules are dancing and frisking about like gnats in 

 the air, and the electrons inside the atoms are still 

 more rapidly changing places. 



We meet with the same staggering figures in the 

 science of the infinitely little that we do in the sci- 

 ence of the infinitely vast. Thus the physicist deals 

 with a quantity of matter a million million times 

 smaller than can be detected in the most delicate 

 chemical balance. Molecules inconceivably small 

 rush about in molecular space inconceivably small. 

 Ramsay calculates how many collisions the mole- 

 cules of gas make with other molecules every sec- 

 ond, which is four and one half quintillions. This 

 staggers the mind like the tremendous revelations of 

 astronomy. Mathematics has no trouble to compute 

 the figures, but our slow, clumsy minds feel helpless 

 before them. In every drop of water we drink, and 

 in every mouthful of air we breathe, there is a move- 

 ment and collision of particles so rapid in every sec- 

 ond of time that it can only be expressed by four 

 with eighteen naughts. If the movement of these 

 particles were attended by friction, or if the energy 

 of their impact were translated into heat, what hot 

 mouthfuls we should have! But the heat, as well 

 as the particles, is infinitesimal, and is not percep- 

 tible. 



192 



