Mrs Welding was my English teacher at St Bernard's Convent Grammar School, in Westcliff-on-Sea. She was a gentle person, small in stature with a quiet voice and always neatly dressed. She wasn't one of those forceful, funny, charismatic teachers who bounced down the aisle making you hysterical with laughter; her style was different. It was gentle and encouraging, never putting anyone down.
It was amazing that, out of such a neat, contained, quiet person, came this explosion of thought and imagination. Mrs Welding absolutely loved her own subject and simply shared it with us, holding nothing back. She had such a gentle, encouraging way of communicating it, with straightforwardness and generosity.
We never did a full-length play at school, but we did have the Shakespeare Cup, a little competition between certain classes. Without any help from teachers, we performed a scene from a Shakespeare play without a set or costumes, just in our school uniforms, and the cup was awarded to the winners.
Spotting my interest in acting, Mrs Welding told me about the National Youth Theatre. Handing me the information and application forms, she guided me again in a quiet and unassuming way.
That was about the length and breadth of my drama experience, although we did put on a nativity play every year. It was directed by a figure of enormous glamour: Miss Angel, the elocution teacher. Our nativity started right at the beginning in the Garden of Eden, and I played Eve for a couple of years. The play was set in stone, and so we all had to say the same lines and make the same moves, probably in the way it had been done for generations. We certainly had to wear the same costumes, which were smelly.
But Mrs Welding was the one. Not only did she introduce me to the National Youth Theatre, but also to Thomas Hardy and Jane Austen and poetry, and all of those other wonderful treasures that we can then access later on in our lives.
As she was so important to me personally, I wrote about Mrs Welding in my autobiography. Around the same time, a dear friend of mine was going to a wedding in Dorset. Giving an incredible sermon that was interesting and uplifting and exciting, the female vicar that day had inspired my friend, who spoke with her about it afterwards.
The vicar said she owed her love of giving sermons to a wonderful lady who taught her at school; an inspirational teacher called Mrs Welding. It seems her gold dust has been spread over many generations and many people. Women in all walks of life will remember Mrs Welding with gratitude.
When my autobiography came out, I visited Mrs Welding and took her a copy. I found her to be the elegant and beautiful little person that she always was. She said she was just doing her job, and remained incredibly modest about her achievements.
What she maybe doesn't realise is that it was the way she did it that made her so special.
Dame Helen Mirren is one of the country's most successful stage, television and film actresses. She has won an Oscar, as well as several Baftas, Emmy Awards and Golden Globes. Her autobiography, In the Frame: My Life in Words and Pictures, is published by Phoenix
She was talking to Paula Barnett