Information that the government held on the LCS from its earliest days in November 1792 listed the "Black Swan Brown's Lane Spitalfields" as a meeting place of Div 17, which was formed on the 6 Nov, and met on that day, and on the 13th Nov "but not suffered to remain."
In the 1770s and 1780s, the Black Swan was home to the Spitalfields Mathematical Society. Records of the Society written in 1784 give some information about its history:
(From The Spitalfields Mathematical Society webpage).
In the year 1772, another Mathematical Society, then held at the Black Swan, Brown's Lane, Spitalfields was, at the request of its members (who brought with them their books and instruments, etc.) incorporated into the Society: and in the year 1782 the Society removed to the aforesaid Black Swan.
According to the Survey of London Brown's Lane changed its name to Hanbury Street in 1876. Census infomation shows there was a pub called the Black Swan at 23 Hanbury Street until 1899, on the north side of the street. The photograph at the top of the page (reproduced in the Survey of London vol 27) shows the house next to it -- 24 Hanbury Street -- before the houses were demolised. A market building currently stands on the site.
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