Mr Gruesome : the suburban village #6

Two memories I cannot reconcile:
what was his name? McTavish, always first
to come to mind... but then Grujon... some name
like that. The reason for the second thought
is this: we called him Gruesome from his name.
But that he came from North the Border there
can be no doubt - while the name Grujon didna.
Just take your pick, I'll leave the choice to you.

World War I, he and his friend are orderlies.
A military hospital.
Mesopotamia. Each day
they'd set out for their odious work,
him tweaking his mind-set to certainty:
Not to catch the dysentery.
He never did. Mind over matter.
We heard this story endless times.
Each day's first lesson would begin with it:
When I was in... The whole class groaned.
From it we were supposed to learn the trick.

For each day's final lesson, though,
he'd mount his desk, a pipe in hand,
and stand above us, beaming down.
He had a store of pipes: Pan pipes
and penny whistles and two flutes -
end blown, and not the sort you'll see these days.
Always in plus fours, he'd start to dance -
tap dance, if he was in the mood -
and we would have to dance
in circles round his desk.
Then statues when the music stopped,
and he would flick the pipe to point it
straight at some quite fearful child and cry:
Spell pneumonia! chrysanthemum!
bronchitis or grammatical!

Get it right and you were early home to tea,
but get it wrong and round you went again.
I'd often had bronchitis and the like -
and knowing them would get me early home

I had to take a doctor's note in once.
I'd had a bout of bronchiectasis.
He peered at it and muttered quite a bit,
then looked at me above his spectacles:
Well lad, your spelling of bronchitis is
spot on, that canna be denied - but this
I'll tell you now: your doctor's spelling is na!