86 
THE FAIRY-LAND OF SCIENCE. 
been drawn into a drop, then its history is very 
different The ordinary force of cohesion has then 
no power over the particles to make them into watery 
globes, but its place is taken by the fairy process of 
" crystallization," and they are formed into beautiful 
white flakes, to fall in 
Fig ' 20 ' a snow - shower. I 
want you to picture 
this process to your- 
selves, for if once you 
can take an interest in 
the wonderful power 
of nature to build up 
crystals, you will be 
astonished how often 
you will meet with 
instances of it, and 
what pleasure it will 
add to your life. 
The particles of 
nearly all substances, 
when left free and 
not hurried, can build 
themselves into crystal 
forms. If you melt salt 
all the water evaporate 
slowly, you will get salt-crystals ; beautiful cubes of 
transparent salt all built on the same pattern. The 
same is true of sugar ; and if you will look at the 
spikes of an ordinary stick of sugar-candy, such as I 
have here, you will see the kind of crystals which 
