One morning after getting up early,Newton began to work at once.He worked on a very difficult problem.When it was time for breakfast,he was still thinking it hard,so he would not go to have breakfast.Mary brought a pan of water and an egg to his room.She was going to boil the egg for him.However,Newton wanted to stay by himself and said,“You can put the egg on the table,I’ll boil it.” Having put the egg beside Newton and his watch on the table,she told him,“You must boil the egg for four minutes and then it will be ready.”Then she came out of the room.