What was the movement to allow more silver in circulation in the late 1800's?

Answer 1

It was known as the "Free Silver Movement" and was backed primarily by farmers and westerners, who were hurt by tight money policies of Eastern bankers.
The leader of the movement was William Jennings Bryan, who ran on the issue in the presidential election of 1896.

http://www.u-s-history.com/pages/h763.html
http://mason.gmu.edu/~dbill/page2.html
http://www.americaslibrary.gov/cgi-bin/page.cgi/aa/leaders/bryan/silver_1
http://partners.nytimes.com/library/politics/camp/18960711convention-dem-ra.html

Answer 2

Parrot is mostly right but the west coast did not want the silver movement. It was mostly farmers and Southerners who wanted to go to the silver standard. The best example of this is to look at the original Wizard of Oz with the silver slippers. This entire story is symbolic of the movement towards the silver standard.