NEW CONCEPTIONS IN SCIENCE 



more than a guess. Still, they guessed wonderful- 

 ly well. In this paper I wish to sketch the steps 

 which, in our modern day, have led by very differ- 

 ent and diverse paths to the same conception. 



Usually, in any reference to atoms, there are 

 bewildering computations as to how many million 

 billion there are, say, in a drop of water. There 

 seems a mania for making out these ultimate par- 

 ticles unimaginably small, and hence of incredible 

 number. They are not. Beginning with some of 

 the familiar things of every-day life, I hope to show 

 that the atom is not so far beyond the visible as 

 one might suppose, and that it is something quite 

 tangible, and thinkable, and real. 



Some painsful genius once figured out that it 

 would take only an ounce of the spider's web, spun 

 into one long thread, to stretch across the Atlan- 

 tic three thousand miles. In former days, this was 

 often cited as an example of the extremely tenuous 

 state which solid matter may assume and still be 

 perfectly continuous. 



But we know now of threads of substance per- 

 haps a thousand times thinner. If, for example, 

 a drop of the white of an egg, or one of the white 

 corpuscles of the blood, or, better still, the micro- 

 scopic cell of protoplasm from which we all spring, 

 be slightly stained, so as to reveal its structure, it 



104 



