To see the pattern best, start with the present and move backward. Eighty years passed between the attack on Pearl Harbor and the attack on Fort Sumter. Eighty-five years passed between Fort Sumter and the signing of the Declaration of Independence. Add two years (to Gettysburg), and you reach President Lincoln’s famous “fourscore and seven years” calculation. Back up again and note that 87 years is also the period between the Declaration and the climax of the colonial Glorious Revolution.
