It was a first impression, but a sufficiently vivid and truthful one, so I give it here.
"CRAYSHAW'S (for that's what they call it here, and a beastly hole it is).
"_Monday_.
"MY DEAR OLD CHARLIE,--We came earlier than was settled, for Father got impatient and there was nothing to stop us, but I don't think old Crayshaw liked our coming so soon.

You never saw such a place, it's so dreary.

A boy showed us straight into the school-room.

There are three rows of double desks running down the room and disgustingly dirty, I don't know what Mrs.Wood would say, and old Crayshaw's desk is in front of the fire, so that he can see all the boys sideways, and it just stops any heat coming to them.

And there he was, and I don't think Father liked the look of him particularly, you never saw an uglier.