The Old Free State, Volume II, by Landon C. Bell records this unusual first name. On p. 342 it reads, Algernon Sidney Jones (born 1807 and died ca. 1857). He is given as the son of Dorothy Anderson and Branch Jones. His marriage in 1836 was to Mary Jane Overton. Their children were Mary Branch, Sidney O., and Joseph Bragg Jones. The marriage is recorded in Lunenburg Co., VA on the 7th of February 1837. I believe that there was someone seeking a connection to the Bragg family. This may be the case.
From the Caroline Cunningham Collection, # 56, Vol. III, p. 6.