Help from my literary and British friends?

[gridlore]

In the wake of HBP and general memories of good young adult fiction, I'm struggling to remember the name of a series of British YA fiction books i treasured as a kid. I think I got them (or Craig got them, and I stole them) from the British grandparents. The books (and there were several) concerns a group of four friends. In their early teens, they have Kipling-esque adventures all over the world. One of them owned a parrot, and one was obsessed with the Great Auk, an extinct seabird. From the writing, I suspect that the books were written in the 1920s or 30s.

Not much to go on, I know, but it's been bugging me for days.

A lot of great stuff from those days. Craig and I devored the Tom Swift series, along with The Hardy Boys and even the wonderfully English Biggles books.