STUDIES IN NATURE 



about the composition of water, it is clear that 

 we shall not always meet with water in the 

 same form. We said that it was always present 

 as invisible vapour in the air, we know it best 

 as 'water,' but we must not forget that the 

 frost will turn it into solid ice, when it again 

 has quite a fresh set of properties. Water, 

 then, can exist in three states : as solid ice, 

 as liquid water, as gaseous vapour. Let us 

 now consider how it differs in these three states 

 of its existence. 



We said before that when it took the form 

 of vapour in the air we could neither see nor 

 consciously touch it. Our reason told us that, 

 like the air, it must be on all sides of us. A 

 slight chilling of the air will sometimes make 

 our vapour come back to us as liquid water. 

 We can now see it and touch it, but we can 

 hardly be said to be able to handle it, for it has 

 no shape of its own, and will take the shape of 

 any vessel or glass it is placed in. A little 

 more chilling, a little more heat taken away 

 from it on a cold frosty night, and our water is 

 changed into ice, which we can see, touch and 

 handle. We break a piece off; it keeps its 

 shape, unless we hold it too long in our warm 

 hands or take it into a hot room, when it begins 

 at once to absorb heat and transform itself back 

 into water. The question whether we shall find 

 our water in the solid, liquid, or gaseous state 

 depends only on the amount of heat there is 



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