What promise caused the constitution to be ratified?

In 1517, the spanish friar bartolomé de las casas, disturbed by the suffering which spanish conquistadores had wrought on the native populations of america, became an important advocate of

Which  was not a problem faced by farmers in the late 19th century

"if i have seen farther than others," said newton, "it is because i have stood on the shoulders of giants." who were the giants to whom newton was referring? could this be said of any scientific accomplishment? explain.