Private
If nothing else, your friends will have been entertained.
Yes, I should like that. I'm better at practical magic. I even made it to the top of the class in Transfiguration a few times. Arithmancy isn't practical at all the way our professor teaches it, though. Only pages of tedious equations.
I'm at [Everdale address] Please have it wrapped first, if you don't mind. Mrs Babbage, the landlady, has a habit of prying too much into magical matters which don't rightly concern her.
Ah. No, you're quite right to say it. Please accept my apologies, I didn't mean to be impolite. I was only very pleased to encounter someone else who knew of Hogwarts, and - well, it isn't an excuse. My name is Arcturus Black, I'm Licorus Black's second son. I find these machines awfully peculiar. I did begin by writing out proper letters on them, but nobody else seems to. Perhaps I ought to, though. It is awfully important to maintain standards.