When we dig into the earth, can we always find water?
Yes; we can always find water.
What reason may be given for believing this?
Because thousands of wells have been dug in different parts of the country, and water is obtained from them.
Are these wells all of the same depth?
No; they vary in depth from four or five feet to eighty or ninety feet.
What makes the water hard in some wells?
When the stream of water passes through iron ore, before reaching the well, it absorbs some of the iron, which makes it hard.
How else may it become hard?
By passing through other mineral substances, such as limestone and sulphur, it will become hard.