8 THE FAIRY-LAND OF SCIENCE. 
and impossible monsters, but imagination, the power 
of making pictures or images in our mind, of that 
which is, though it is invisible to us. Most children 
have this glorious gift, and love to picture to them- 
selves all that is told them, and to hear the same tale 
over and over again till they see every bit of it as if it 
were real. This is why they are sure to love science 
if its tales are told them aright; and I, for one, hope 
the day may never come when we may lose that child- 
ish clearness of .vision, which enables us through the 
temporal things which are seen, to realize those eternal 
truths which are unseen. 
If you have this gift of imagination come with me, 
and in these lectures we will look for the invisible 
fairies of nature. 
Watch a shower of rain. Where do the drops come 
from? and why are they round, or rather slightly 
oval? In our fourth lecture we shall see that the 
little particles of water of which the rain-drops are 
made, were held apart and invisible in the air by heat, 
one of the most wonderful of our forces * or fairies, 
till the cold wind passed by and chilled the air. Then, 
when there was no longer so much heat, another 
invisible force, cohesion, which is always ready and 
waiting, seized on the tiny particles at once, and 
locked them together in a drop, the closest form in 
which they could lie. Then as the drops became 
* I am quite aware of the danger incurred by using this word 
" force," especially in the plural ; and how even the most mod- 
est little book may suffer at the hands of scientific purists by 
employing it rashly. As, however, the better term "energy" 
would not serve here, I hope I may be forgiven for retaining 
the much-abused term, especially as I sin in very good company. 
