Benjamin Franklin  (January 17, 1706 [O.S. January 6, 1705] -  April 17, 1790) was an American polymath and one of the Founding Fathers of the United States. Franklin was a leading author, printer, political theorist, politician, freemason, postmaster, scientist, inventor, humorist, civic activist, statesman, and diplomat.

In 1727, Benjamin Franklin, then 21, created the Junto, a group of "like minded aspiring artisans and tradesmen who hoped to improve themselves while they improved their community." The Junto was a discussion group for issues of the day; it subsequently gave rise to many organizations in Philadelphia. The Junto was modeled after English coffeehouses that Franklin knew well, and which had become the center of the spread of Enlightenment ideas in Britain.  Reading was a great pastime of the Junto, but books were rare and expensive. The members created a library initially assembled from their own books after Franklin wrote:  A proposition was made by me that since our books were often referr'd to in our disquisitions upon the inquiries, it might be convenient for us to have them altogether where we met, that upon occasion they might be consulted; and by thus clubbing our books to a common library, we should, while we lik'd to keep them together, have each of us the advantage of using the books of all the other members, which would be nearly as beneficial as if each owned the whole.  This did not suffice, however. Franklin conceived the idea of a subscription library, which would pool the funds of the members to buy books for all to read. This was the birth of the Library Company of Philadelphia: its charter was composed by Franklin in 1731. In 1732, Franklin hired the first American librarian, Louis Timothee. The Library Company is now a great scholarly and research library.

Using a quote from the above article, answer the following question: When did this take place?
1731.