McMahon was the son of Lieutenant-General Charles Alexander McMahon, FRS, FGS , a geologist and Commissioner of both Lahore and Hisar in British India, and who, like his father Captain Alexander McMahon had been an officer with the East India Company. The McMahons are the Gaelic clan of Mac Mathghamhna who had come originally from the medieval Irish kingdom of Airgíalla or Oriel in South Ulster/North Leinster, where they reigned from around 1250 until about 1600. Wikipedia*
On the C-SPAN Networks:
Henry McMahon has one video in the C-SPAN Video Library; the first appearance was a 1995 House Committee.