During the June 26th clean-up in 2009, a portion of a bottle from the "Libby, McNeill & Libby" company was discovered by a volunteer. It has a incorporation date of 1883 embossed on it and the company itself was founded in 1869. Based on information from bottle collectors it is believed to have been from a milk bottle. Below is a photograph of the artifact.

Information from Wikipedia does not state when the company was incorporated but the finding of this bottle helps us to figure it out.
For more information visit:
http://en.wikipedia.org/wiki/Libby's