Miss Bryden was an imposing figure clad in many yards of black bombazine held together perilously by a cameo brooch, which perched on her massive bosom.

She was my class teacher at Hillhead Primary School in Glasgow when I was 10 and her influence remains with me to this day.

Fresh-faced, without a trace of make-up and her hair scraped back into a forbidding bun, her voice would rise to a screech when she wanted to emphasise something. But she was a fine teacher, a big woman with a big heart and dedicated to her students and her profession.

I still call her Miss Bryden because I never knew her first name. Such familiarity was not encouraged with the lady teachers of my primary school. They were almost all spinsters whose chances of marriage had no doubt been affected by the carnage of the First World War.

It was a very traditional primary education. We sat at wooden desks with inkwells, pens with scratchy nibs, and few of the modern attractions of the classroom.

Miss Bryden was a stickler for proper pronunciation, sentence construction and good grammar. Woe betide you if you made a mistake in any of these areas. Political correctness today would not allow the sharp slap on the knuckles with a ruler, which was her ultimate means of expressing displeasure.

Although the strap was used for corporal punishment in Scottish primary schools at that time, the sheer force of Miss Bryden’s personality, and the disappointment she would express at any failure, were more than enough incentive for me to try to do my best.

I was in awe of her, as were the rest of my classmates, but she was generous and had an unquenchable determination to inculcate her students with self-discipline and application.

Nowadays, she would be regarded as part of an outmoded and insensitive system. Achievement was everything and those who could not keep up with her high standards often felt the wrong side of her tongue. To be accorded praise or encouragement from her was an achievement in itself.

She taught me that rigour in language is as important as it is in science or mathematics. Every Friday morning she would write a long, complicated sentence on the blackboard and we had to divide it into subject, verb and predicate.

She considered splitting an infinitive to be like embracing the Antichrist. Finishing a sentence with a preposition was a terrible sin, and beginning one with a conjunction was beyond the pale. It was no coincidence that I studied Latin and Greek, languages with strict structures and rules, for my Highers.

She did not appear to have any interest in sport, which was soon to become my consuming passion. I don’t think she would have approved of my athletics career, although she might have appreciated the self-discipline that took me to the Olympic Games in Tokyo in 1964.

Miss Bryden’s teaching had a profound influence on my life. She also taught me about the virtue of hard work, although I don’t think I really worked as hard as I had for her until after I started at the Bar as a young advocate in Scotland.

So many of the things I have done since those days - writing, speaking in public, speaking politically - had their origins in the way she taught me English language.

I lost touch with Miss Bryden after primary school, but although her physical presence has faded into the background, her influence remains as strong today as it ever was. And I can still hear that high-pitched screech if ever I am foolish enough to split an infinitive.

Sir Menzies Campbell was talking to David Harrison.

Personal profile

Born: Glasgow, 22 May 1941

Education: Hillhead Primary School, Hillhead High School, Glasgow; University of Glasgow; Stanford University, California

Career: Olympic athlete, lawyer, Liberal Democrat MP and party leader, 2006-07.