If he is the person I am thinking of, then he also tried to teach some of us Russian. After "A' levels. I think.
I have probably mentioned it before, but he was always late for the class, which took place after the morning break in Pop Massen's classroom at the end of the Maths block.
One day at about 11.05, we gave up on him and one by one, went downstairs and back to house via the quarter mile.
As I left, I noticed him standing under the arch, watching us all leave.
The next week, he arrived before 11.00, (the class started at 10.55), but nothing was said at all.
CH seemed to give introduction course like that. I seem to remember J C Todd trying to teach us modern Greek.