The Constitution was written by James Madison who was a Senator. But the constitution wasn't put into effect unless it was ratified. So all of the other senators from the rest of the country had to decide weither the Constitution should have been put into power. In the end, the constitution was ratified, so it was put into power. The majority of the 100 senators (2 senators per state) said that the Constitution should be put into power but only if a list of right's would be added to the Constitution. So the senators added a list of 10 rights to the constitution. And those rights (or amendments) were put into a specal document called the Bill of Rights. And over time, Senators added 17 amendments to make a total of 27 amendments!