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Here is a link to the 1858 Griffiths Valuation head of household listing for Kilmacshalgan civil parish and five Brownes are listed. http://www.failteromhat.com/griffiths/sligo/kilmacshalgan.htm The place name you mention in 1807 is not an offical townland in Kilmacshalgan. The 1901 and 1911 census records for the parish still show Brown families in the parish. We do not have any data bases after 1911. I did check the online Irish phone book and there were no browns listed in the area. However, the online directory is only a partial list of phone users.