Here some prominent features of the earth have been mentioned which remind man of God in order to make him a grateful servant of God. One of these is the mountain ranges that have risen up on the surface of the earth in order to keep the dense matter beneath the seas well-balanced. Probably this refers to what is known as ‘isostasy’ in modern science. Similarly, it is also a sign of God that the earth is so made that man is able to make roadways sometimes on level plains, and sometimes as passages between mountains and rivers. The roof of the sky, which is our upper atmosphere, is composed in such a way as to prevent certain harmful rays of the sun from affecting us in the form of the ozone layer. The atmosphere also prevents the majority of the continuous shower of meteorites from reaching us. In the same way, there are signs in the moving of the sun and the moon in their orbits without clashing with each other, resulting in the regular occurrence of day and night on the earth. Innumerable such signs are found on the earth. If man examines them in depth, he will be overwhelmed by the realisation of God’s blessings and His powers. But he ignores them. Even after seeing clear events and signs, he continues to turn a deaf ear and a blind eye to them.