Marguerite Janet Smithson born May 1860 in New York married David Langridge from Mereworth, England, 5 Oct 1880, in Hoboken, New Jersey. Their son William Henry Russell Langridge was born in Philadelphia, Pennsylvania, 5 Sep 1881, and grew up in the Bronx, Westchester County, New York. Marguerite (or Margaret, as her name is found in several records) married a C. James McNally after the death of her first husband (probably 16 Apr 1887 in NYC) and they lived in Westchester County, at least for a while.
According to family lore, Marguerite was related to James Smithson of the Smithsonian Museum.
Perhaps the birth of William Henry Russell Langridge I in 1881 Philadelphia has no relation to Smithsons or Langridges there. However, if you're aware of any connection I'd greatly appreciate hearing from you.
Thanks again to the Philadelphia genealogy forum members who helped me get this far.