At the time PG wrote the school stories, and for many years later, boys at Public and Grammar schools referred to each other by surname. Only close friends would use first names, although nicknames would be used more freely. Masters, of course, called boys by surname but the servants and other employees would use surname plus Mister or Master according to age. Everyone knew their place! The tag 'major' was used to denote the eldest boy with a surname shared with another, often a brother. Second in age would be 'minor' and a third 'minimus'. In English - greater, smaller, smallest. I have no idea what a fourth would be called.
A lot of PG's schools have headmasters who are also Reverends. I don't know how common that was or whether Wodehouse was affected by one in particular. For what it's worth, the headmaster of the school I attended (Grammar, not public) was a Doctor of Divinity. He took Religious Knowledge lessons for all first year boys as a way of getting to know them. He passed away in 2004.
See also the page on public schools.
